s

S

safe fat resource: A fat resource that contains extra classic 68K code at its entry point to check for the presence of the Code Fragment Manager. This guards against calling the Mixed Mode trap when the Mixed Mode Manager is not present

See also: fat resource

SAM

See: service access module (SAM)

sample

See: sample point

sampled sound: Any sound defined using sampled-sound data.

sampled sound header: A sound header that can describe monophonic, noncompressed sampled-sound data. Defined by the SoundHeader data type

See also: compressed sound header, extended sound header

sampled-sound data: Any set of values that represent the sample points of a sampled sound. The values can be in either offset-binary format or two's complement format.

sample frame: An interleaved set of sample points (for noncompressed sampled-sound data) or packets (for compressed sampled-sound data).

sample number: A number that identifies the sample with data for a specified time.

sample point: (1) A value representing the amplitude of sampled-sound data at a particular instant. One or more sample points make up a sample frame of noncompressed sampled-sound data

sample rate: The rate at which samples are recorded. Sample rates are usually measured in kilohertz or megahertz.

sampling: The process of representing a sound by measuring its amplitude at discrete points in time

See also: recording

SANE

See: Standard Apple Numerics Environment (SANE)

saturation: The degree of hue in a color or a color's strength. A neutral gray is considered to have zero saturation. A saturated red would have the a color similar to apple red

saturation matching: A rendering intent in which the relative saturation of colors is maintained from gamut to gamut. Colors outside the gamut are usually converted to colors with the same saturation, but different lightness, at the edge of the gamut.

saturation value: A setting that controls color intensity. For example, at high saturation levels, red appears to be red; at low saturation, red appears pink. Valid saturation values range from 0 to 65,535, where 0 is the minimum saturation value and 65,535 specifies maximum saturation. Saturation value is set with the video digitizer component's VDSetSaturation function.

saved registers area: The area in a PowerPC stack frame that holds the saved values of the nonvolatile general-purpose and floating-point registers.

scale: To proportionally enlarge or shrink. A mapping can be used to scale the geometry of a shape, about a fixed origin, either horizontally or vertically.

scaling: The adjustment in size or shape of the glyphs of a font. The Font Manager performs both implicit scaling and explicit scaling, at the request of QuickDraw.

scaling factor: A specific scale that you force onto a style run to create custom kerning

See also: kerning adjustments array, point size factor

scatter/gather list: A SCSI Manager 4.3 data type consisting of one or more elements, each of which describes the location and size of one data buffer.

SCB

See: session control block (SCB)

scrap: A storage area (either in memory or on disk) that is available to applications to hold the last data cut or copied by the user.

Scrap Manager: A collection of routines that your application can use to support copy-and-paste operations.

scrap translation list: A list of source and destination scrap types among which a scrap translation system can translate. Defined by the ScrapTranslationList data type.

scrap translation system: A translation system that can recognize and translate scraps from one format to another.

scrap type specification: A way of specifying information about translating a scrap. Defined by the ScrapTypeSpec data type.

scratch file: Backing store for temporary data not associated with a permanent disk file

See also: memory-mapped file

script: (1) Any collection of data that, when executed by the appropriate program, causes a corresponding action or series of actions. When a scripting component that supports the OSA executes a script, it sends Apple events as necessary to trigger actions in server applications. (3) A method for depicting words visually

See also: script system

scriptable application: An application that can respond as a server application to Apple events sent to it by scripting components. To be scriptable, an application must respond to the appropriate standard Apple events, and it must provide an 'aete' resource that describes the nature of that support

See also: Apple event user terminology resources

scripting: Writing and executing scripts to control the behavior of multiple applications.

scripting component: A component that responds appropriately to calls made to the standard scripting component routines. Most scripting components implement scripting languages; for example, the AppleScript component implements the AppleScript scripting language.

script application: A script file with the file type 'APPL' that contains the script data as a resource of type 'scpt'. If a script application has the creator signature 'aplt', a user can double-click its icon to trigger the script. If a script application has the creator signature 'dplt', a user can drag the icon for another file or a folder over the script application's icon to trigger its script. By default, when a user triggers the script in a script application, a splash screen appears that allows the user either to quit or to run the script. Users can also save a script application in a form that bypasses the splash screen, running the script immediately after the user double-clicks its icon.

script application component: A component registered with the Component Manager at system startup. When a user opens a script application, the script application component loads the script and passes the resulting script ID to the appropriate scripting component for execution.

script code: A number indicating a particular script system on the Macintosh. Constants are defined for each of the script codes recognized by the Macintosh script management system.

script comment: A description, in a script editor window, of what the script displayed in that window does.

script context: A form of script that maintains context information for the execution of other scripts. A script context can also be used to handle Apple events. Like a compiled script, a script context can be decompiled as source data. In the AppleScript scripting language, a script context is called a script object.

script data: A compiled script, script value, script context, or any other representation of a script in memory used internally by a scripting component

See also: compiled script, script context, script value

script editor: An application that allows users to record, edit, save, and execute scripts; for example, the Script Editor application provided with AppleScript.

script extension: A part of the Macintosh script management system that allows for convenient and efficient creation of new script systems. Each script system provides tables in its international resources that specify the proper text-manipulation and formatting behavior; the script extension interprets those tables when an application makes a text-related call. There are two script extensions: WorldScript I, the universal 1-byte script system extension, and WorldScript II, the universal 2-byte script system extension.

script file: A file in which a script is stored. A script file can be a compiled script file, a script application file, or a script text file.

script ID: A data structure of type OSAID"that is, a long integer"used by scripting components to keep track of script data.

Script Manager: The part of the Macintosh system software that manages script systems.

script object: AppleScript term for script context

See also: script context

script record: A private data structure, maintained by the script management system, that defines each enabled script system, and through which calls to that script system are dispatched.

script run: A sequence of text that is contiguous in memory and belongs to a single script system.

script system: A collection of software facilities that provides for the representation of a specific writing system. It consists of a set of keyboard resources, a set of international resources, one or more fonts, and possibly a script system extension (1-byte or 2-byte). Script systems include Roman, Japanese, Arabic, Traditional Chinese, Simplified Chinese, Hebrew, Greek, Thai, and Korean. Types of script systems include 1-byte simple, 1-byte complex, and 2-byte.

script text file: Uncompiled statements in a scripting language saved by a script editor as a text file. A user must open a script text file in a script editor and successfully compile it before it will execute

See also: script editor

script utility: The low-level equivalent to one of a large group of script-aware Script Manager, Text Utilities, or QuickDraw text routines. Some script utilities are handled by the script management system; others are passed on to script systems. Script utilities all use the _ScriptUtil trap.

script value: An integer, a string, a Boolean value, a constant, a 'PICT', or any other fixed data that a scripting component returns or uses in the course of executing a script.

script-aware: Said of a routine or system-software manager that takes the current script system into account when manipulating or displaying text.

script-defaulted result flag: A Script Manager variable that indicates whether the system script has replaced the font script due to the unavailability of the font script.

script-forced result flag: A Script Manager variable that indicates whether the system script has replaced the font script due to font forcing.

script-language record: A record that defines a script and language supported by a text service component.

script-language support record: An array of script-language records that defines all the scripts and languages supported by a text service component.

script-sorting resource: An international resource, of type 'itlm'. The script-sorting resource lists all defined script codes, language codes, and region codes, in proper sorting order. It also maps each region to its parent language, and each language to its parent script. An application uses the script-sorting resource to sort multiple-language lists. There is only one script-sorting resource for each version of the Macintosh system software.

scrolling list: A list of user-selectable items that can be scrolled if it is longer than the available display area.

scroll arrow: An arrow at either end of a scroll bar. When the user clicks a scroll arrow, the application moves a document or list by one unit of measure in the direction of the arrow. When the user holds the mouse button down while the cursor is over a scroll arrow, the application moves the document or list continuously in the direction of the arrow.

scroll bar: A rectangular bar that may be along the right or bottom of a window or list box. Clicking or dragging in the scroll bar causes the view of the window or list box to change

See also: scroll arrow, scroll box

scroll box: The part of a scroll bar that indicates position or value. Scroll boxes are also known as 'indicators' or 'thumbs.' See also ghost, indicator, scroll bar.

SCSI

See: Small Computer System Interface (SCSI)

SCSI bus: A bus that conforms to the physical and electrical specifications of the SCSI standard.

SCSI command: An instruction from an initiator to a target to conduct an operation, such as reading or writing a block of data

See also: command phase

SCSI device: A device connected to the SCSI bus, either a peripheral device or a computer.

SCSI ID: An integer value from 0 to 7 that uniquely identifies a device during SCSI transactions.

SCSI interface module (SIM): A software module between the transport (XPT) and the host bus adapter (HBA) in SCSI Manager 4.3. The SIM processes and executes SCSI requests, and provides a hardware-independent interface to the HBA.

SCSI Manager: The part of the Mac OS that controls the exchange of information between a Macintosh computer and peripheral devices connected through the Small Computer System Interface (SCSI).

SCSI message: Information exchanged by the target and initiator at the completion of a SCSI transaction

See also: message phase

search key: A piece of data that the File Manager uses when searching through a B*-tree to locate the information it needs.

search privileges

SECAM

secondary caret: The low caret that is displayed at the secondary caret position; part of a dual caret.

secondary caret position: The screen location (denoted by the secondary caret) associated with the character that has an opposing direction from the primary line direction.

secondary script

See: auxiliary script

secret-key cryptography: A system of cryptography in which a single key is used to both encrypt and decrypt data. All who wish to share information must share the same key and keep it secret from all others.

section: (1) A storage unit in a PEF container that contains object code or data. PEF containers usually contain multiple sections. (2) A region of memory occupied by part of a loaded fragment. When a fragment is loaded, it is divided into a code section and one or more copies of the data section

See also: code section

section header: A data structure in a PEF container that contains information (size, alignment, and so on) about the sections stored within it.

secure session: An ADSP session that uses ASDSP to perform an authentication process in which the identities of the users at both ends of the connection are verified. Users can exchange data over a secure session, and direct ASDSP to encrypt the data before transmitting it and decrypt the data before delivering to the recipient.

seed: An initialization value used by a random number generator to produce a sequence of values.

See Files privileges: The directory access privileges that allow users to read files in the specified directory.

See Folders privileges: The directory access privileges that allow users to see other directories in the specified directory.

segment: A named collection of modules in 68K-based runtime programs.

segment header: A collection of fields that provides information about a segment. In the classic 68K near model architecture, it describes the location of the jump table and the number of jump table entries.

segment location record: A data structure that provides information about the location of a fragment in the resource fork of a file on disk. Defined by the SegmentedFragment data type.

Segment Manager: The part of the Mac OS that loads and unloads the code segments of a 680x0 application into and out of memory.

segment relocation information: Part of a segment header used to store information that allows the relocation of intrasegment references for programs compiled and linked using the -model far option.

selection duration: A time value that specifies the duration of the current selection of a movie.

selection phase: The phase in which a SCSI initiator selects the target device for a transaction.

selection range: The series of characters in memory where the next editing operation is to occur. The onscreen glyphs of those characters are commonly highlighted. The characters in a selection range are always contiguous in memory, but their glyphs are not necessarily so on screen.

selection time: A time value that specifies the starting point of the current selection of a movie.

selector: (1) An integer value that controls the function of a multipurpose routine. For example, the Script Manager uses selectors to figure out which variable you want to read when calling GetScriptManagerVariable

See also: selector code

selector code: A parameter to the Gestalt function that specifies what information about the operating environment the caller requires

See also: environmental selector, informational selector

selector function: A function that is executed when an application calls Gestalt and passes the associated selector code.

selector-based trap: A system software routine that is called by passing a selector code to a single trap macro.

semantic type: The widest type of the operands of an expression.

SendReset: An ADB command that instructs all ADB devices to reset themselves to their startup states

See also: Flush, Listen, Talk

send function: A function called by a scripting component whenever it sends an Apple event during script execution. You can provide an alternative send function if you want your application to perform some action instead of or in addition to sending Apple events. If you don't provide an alternative send function, scripting components call the standard Apple Event Manager function AESend with default parameters.

send queue: A buffer in which ADSP stores the bytes of data being sent until the remote connection end acknowledges their receipt.

separator line: A control that provides a way to separate elements in a dialog box with a simple horizontal or vertical line.

sequence: A series of images that may be compressed as a sequence. To do this, the images must share an image description structure. In other words, each image or frame in the sequence must have the same compressor type, pixel depth, color lookup table, and boundary dimensions.

sequence grabber channel component: A component that manipulates captured data for sequence grabber components.

sequence grabber component: A component that allows applications to obtain digitized data from sources that are external to a Macintosh computer. For example, you can use a sequence grabber component to record video data from a video digitizer component. Your application can then request that the sequence grabber store the captured video data in a QuickTime movie. In this manner you can acquire movie data from various sources that can augment the movie data you create by other means, such as computer animation. You can also use sequence grabber components to obtain and display data from external sources, without saving the captured data in a movie.

sequence grabber panel component: A component that allows sequence grabber components to obtain configuration information from the user for a particular sequence grabber channel component. An application never calls a sequence grabber panel component directly; application developers use panel components only by calling the sequence grabber component.

Serial Driver: The part of the Mac OS that provides low-level support for asynchronous, interrupt-driven serial data transfers through the modem and printer ports.

serif: The fine lines stemming from and at an angle to the upper and lower ends of the main strokes of a letter"for example, the little 'feet' on the bottom of the vertical strokes in the uppercase letter M in Times Roman typeface.

server: A computer or program dedicated to performing tasks or providing resources, generally in response to client requests.

server application: An application that responds to Apple events requesting a service or information sent by client applications or scripting components (for example, by printing a list of files, checking the spelling of a list of words, or performing a numeric calculation). Apple event servers and clients can reside on the same local computer or on remote computers connected to a network.

server MSAM (SMSAM): An MSAM that transfers messages for multiple users on the AppleTalk network to which it is connected. It transfers messages between a PowerShare mail server and an external messaging system. A server MSAM must run on the same Macintosh as a PowerShare mail server

server node ID: A node ID that falls within the numeric range of 128_254 ($80_$FE). An application or process must explicitly request a node ID within the server range by making an extended Open call and setting to 1 the high bit (bit 31) of the extension ioMix field.

service: To handle an interrupt by executing its interrupt handler.

service access module (SAM): A software component that provides a PowerTalk user with access to external mail and messaging services or catalog services.

service request signal (SRQ): A signal sent by an ADB device to inform the ADB Manager that it has data to send.

session: (1) A logical (as opposed to physical) connection between two entities (such as a Macintosh program and a database server) that facilitates the transmission of information between the two entities. (2) In the PPC Toolbox, an exchange of information between one open application with a port and another open application with a port. Sessions can occur between applications that are located on the same computer or across a network. An application has the option to accept or reject a session request. Authentication of the requesting user may be required before a session can commence

See also: authentication, message block, port, Java runtime session

session control block (SCB): A block of memory that an ASP workstation client application must allocate for the .XPP driver to use internally to manage a session.

session establishment: The process of setting up a connection over which a dialog between two applications or processes can occur. Session-oriented protocols provide this service.

session ID: A number that uniquely identifies a session.

session key: A unique key that the AOCE authentication server generates and returns to the ASDSP initiator in a secure manner. The authentication server generates the session key exclusively for use by the authentication process for the session that the initiator attempts to open. The session key is valid for a limited time only.

session listening socket (SLS): A socket that the ASP server uses to listen for incoming session requests.

session reference number: A unique session identifier that ASP assigns to a session that it opens successfully. The ASP server uses this number to distinguish between communication from various concurrent sessions.

Setup catalog

See: PowerTalk Setup catalog

Setup record: A record in the PowerTalk Setup catalog containing record references to all records in the PowerTalk Setup catalog that represent slots, catalogs, and other items.

setup template: A set of AOCE templates that allow a user to install and configure a service access module.

shadow library: A small stub library that can load a larger import library on demand.

shadow sync sample: A self-contained sample that is an alternate for an already existing frame difference sample. During certain random access operations, a shadow sync sample is used instead of a normal key frame, which may be very far away from the desired frame

See also: frame differencing

shape: (1) A graphic or typographic item (such as a geometric shape, a bitmap, or a line of text) created and drawn with QuickDraw GX. (2) A set of QuickDraw GX objects that, taken together, describe the type and characteristics of such a graphic or typographic item. A shape consists of a shape object, a style object, an ink object, and a transform object.

shape attributes: A group of flags that modify the behavior of a shape object.

shape cache: A cache created and maintained by QuickDraw GX for storing the results of intermediate calculations made prior to drawing a shape.

shape fill: A property of a shape object. The shape fill specifies whether and how QuickDraw GX fills in the outlines of a shape that it draws.

shape object: A QuickDraw GX object that, along with several other objects, describes a QuickDraw GX shape. A shape object specifies the fundamental type and contents of a shape.

shape part: A designation of a part of a shape or its geometry (such as bounding rectangle or corner point) that can be considered in hit-testing

See also: tolerance

shape type: A property of a shape object. The shape type specifies the classification (such as point, line, bitmap, or text) of a particular shape.

shape-parts mask: For hit-testing, the list of shape parts to be tested against the hit point

See also: tolerance

shared access: The file access permissions that allow other users both read and write access to a file.

shared environment: Any operating environment that supports multiple users and multiple access to data or applications.

shared library: A fragment that exports functions and global variables to other fragments. A shared library is not included with the application code at link time but is linked in dynamically"that is, at program-execution time instead of at program-generation time. A shared library is stored in a file of type 'shlb'. There are two types of shared libraries: import libraries and plug-ins.

shared library transition vector: An 8-byte transition vector in the CFM-68K runtime environment. Its two fields contain the address of a function and the value to be placed in A5 when the function executes. A transition vector for a flattened shared library is identical to the PowerPC transition vector

See also: application transition vector, transition vector

share point: A volume or directory made available for sharing on the network.

sharing

See: object sharing

sharp join: A join attribute specifying that a shape should be drawn with sharp corners.

Shift-click: To click while the Shift key is down. The Shift key modifies what a simple click does in a given situation _ for example, when a user is selecting items in a list, Shift-clicking extends or shortens the selection.

short number: A 16-bit signed integer with 16 bits to the left and 0-bits to the right of the binary decimal point. A fixed point number with a bias of 0. The short number for 1.0 is 0x0001.

shrink limit: The maximum amount by which glyphs of a given priority may be compressed during justification, before processing passes to glyphs of lower priority

See also: grow limit

Shutdown Manager: The part of the Mac OS that manages the final stages of shutting down or restarting a Macintosh computer.

shutdown procedure: An custom procedure installed by calling the ShutDwnInstall procedure and executed by the Shutdown Manager before the computer restarts or shuts down.

sifter

See: sound component

sign: As used by the Digital Signature Manager: To create a digital signature and affix it to a document or other piece of data. By signing, the signer authorizes the content of the data, protects it from alteration, and asserts his or her identity as the signer.

signaling NaN: A NaN that signals an invalid exception when the NaN is an operand of an arithmetic operation. If no halt occurs, a quiet NaN is produced for the result. No PowerPC Numerics operation creates signaling NaNs.

signature: (1) A value, typically a four-character sequence, that uniquely identifies a program to the Finder or other programs. All signatures must be registered with Apple Developer Technical Support

See also: creator code, digital signature

signature resource: A resource in an AOCE template that specifies the type of the template and the base ID number for the template. Other standard template resources have ID numbers equal to the signature resource's ID number plus some offset value.

signed certificate: A public-key certificate that has been digitally signed by its issuer. Like any digital signature, the signature on a certificate ensures the integrity of the certificate (including its public key) and proves the identity of the signer (the issuer of the certificate).

signed digest

See: encrypted digest

signer: The individual or organization that signs a document or other piece of data. To create a signature, a signer must be the owner of a public-key certificate.

signer file: A file used by a signer to create a digital signature. It consists of the signer's encrypted private key and the signer's certificate set.

significand: The part of a binary floating-point number that indicates where the number falls between two successive powers of 2. The wider the significand field in a numeric format, the more precision the format has.

sign bit: The bit of a single, double, or double-double number that indicates the number's sign: 0 indicates a positive number; 1, a negative number.

SIM

See: SCSI interface module (SIM)

simple expression: An expression containing one floating-point operation.

Simple Mail Transfer Protocol (SMTP): A protocol for the exchange of electronic mail. Computers connected to the Internet often use this protocol.

simple script system

See: 1-byte simple script system

simplify: To remove crossed and overlapping contours from a geometry.

single caret: In unidirectional text, the standard text-insertion caret. In mixed-directional text, one caret that appears at the place where the user will insert the next character, given the current keyboard script. At a boundary between two direction runs, the single caret can correspond to either the primary line direction or the secondary line direction. Because changing the keyboard script in that situation changes the caret location, the single caret is also called a moving caret or jumping caret

See also: dual caret

single format: A 32-bit application data format for storing floating-point values that have a precision of up to seven or eight decimal digits. It is used by engineering applications, among others.

single-fork movie file: A QuickTime movie file that stores both the movie data and the movie resource in the data fork of the movie file. You can use single-fork movie files to ease the exchange of QuickTime movie data between Macintosh computers and other computer systems

See also: movie file

single-writer access: The file access permissions that deny other users write access to a file but allow them to read it.

size box: A box in the lower corner of windows that can be resized. Dragging the size box resizes the window.

size correction: The number of unused bytes at the end of the block, beyond the end of the block's contents.

size region: The area occupied by a window's size box

See also: size box

size resource: A resource (of type 'SIZE') that specifies the operating characteristics, minimum partition size, and preferred partition size of an application.

skew: To progressively distort in a shearing manner. A mapping can be used to skew a shape, about a fixed origin, either horizontally or vertically.

sleep demand: A message from the Power Manager that informs a sleep procedure that the Power Manager is about to put the computer into the sleep state.

sleep procedure: A procedure that the Power Manager calls before it puts a portable Macintosh computer into the sleep state or returns it to the operating state. Sleep procedures are maintained in the sleep queue.

sleep procedure selector code: An integer passed (in register D0) to a sleep procedure that specifies whether the procedure is being called with a sleep request, a sleep demand, a wakeup demand, or a sleep-request revocation.

sleep queue: An operating-system queue that contains pointers to all currently installed sleep procedures.

sleep queue record: A data structure that contains information about a sleep procedure. Defined by the SleepQRec data type.

sleep request: A message from the Power Manager that informs a sleep procedure that the Power Manager would like to put the computer into the sleep state. The sleep procedure has the option of denying this request.

sleep state: A power conservation state of portable Macintosh computers in which the Power Manager and the various device drivers shut off power or remove clocks from the computer's various subsystems, including the CPU, RAM, ROM, and I/O ports

See also: idle state, power-saver state

sleep-request revocation: A message from the Power Manager that informs a sleep procedure that the Power Manager has canceled a sleep request. The procedure can then reverse any changes it made in response to the sleep request.

slider: A type of track control that graphically represents a range of values and allows the user to set the values with an indicator

See also: indicator

slop: In justified text, the amount of space (in pixels) that must be added to a line of text to make it exactly fit the desired line length. The slop value for a line is to be distributed among the style runs, words, and characters on the line.

slot: (1) A connector attached to the processor bus or the NuBus expansion interface. (2) A region in address space allocated to a physical slot. (3) A collection of information about one account on an external messaging system. The information includes whatever is necessary to allow an MSAM to access the account and retrieve and send messages

See also: mail slot, messaging slot

slot ID: The hexadecimal digit corresponding to each card slot. For Macintosh computers with the NuBus expansion interface, each slot ID number is established by the main logic board of the computer and communicated to the card through the /IDx signals.

slot information record: A Slot Manager data structure containing information about a slot. If a card is installed, the slot information record contains the card's initialization status, a pointer to the sResource directory, and other information.

Slot Manager: The set of Mac OS routines that communicate with an expansion card's declaration ROM and allow applications to access expansion cards.

slot resource

See: sResource

slot resource table (SRT): A private Slot Manager data structure that lists all of the sResource data structures currently available to the system. Applications and device drivers use Slot Manager routines to get information from the slot resource table.

slot space: The address space assigned to expansion cards in Macintosh computers

See also: standard slot space, super slot space

slot-based VBL task: A VBL task that is linked to an external video monitor.

slot-card interrupt: An interrupt sent by a slot device.

SLS

See: session listening socket (SLS)

small character set: A character set with no more than 256 characters. Roman, Hebrew, and Arabic have small character sets. The script system for such a writing system needs only 1-byte character codes, and is therefore called a 1-byte script system.

Small Computer System Interface (SCSI): An industry standard parallel data bus that provides a consistent method of connecting computers and peripheral devices.

small icon resource: A resource of type 'SICN' that describes 12-by-16 pixel icons, even though the icons are stored in the resource as 16-by-16 pixel bitmaps. An 'SICN' resource consists of a list of 16-by-16 pixel bitmaps for black-and-white icons; by convention, the list includes only two bitmaps, and the second bitmap is considered a mask. You can use resources of type 'SICN' in menus. Note that the Finder does not use or display any resources that you create of type 'SICN'. To create an icon for display by the Finder, create one or more of the icons in an icon family

See also: color icon resource, icon family, icon resource

smart swash: A variation of an existing glyph (often ornamental) that is contextual

See also: swash

smearing

See: byte smearing

SMP

See: symmetric multiprocessor (SMP)

SMSAM

See: server MSAM (SMSAM)

SMTP

See: Simple Mail Transfer Protocol (SMTP)

SNAP

See: subnetwork access protocol (SNAP)

snapshot format

See: image block

socket: A piece of software that serves as an addressable entity on a node. Applications and processes send and receive data through sockets

See also: statically assigned socket, dynamically assigned socket

socket client: An application or process that is associated with a socket and that sends and receives data through the socket.

socket listener: A piece of assembly-language code that a socket client application provides that receives datagrams that are addressed to that socket.

socket number: An 8-bit number that identifies a socket. A socket number is one of the three parts that together constitute an AppleTalk internet address.

socket table: A table that DDP builds and maintains that contains entries for open sockets; each entry identifies the socket number and the socket listener that are associated with it.

soft import

See: weak symbol

solid fill: A shape fill that indicates a shape's geometry describes an area"the area surrounded by the contours of the shape's geometry. Solid fills include even-odd fill, winding fill, inverse even-odd fill, and inverse winding fill.

solid shape: A shape that describes an area"the area surrounded by the contours of the shape's geometry. The shape fill of a solid shape can be even-odd shape fill, winding-number shape fill, or one of the inverse shape fills.

sorting hook: A routine in the string-manipulation ('itl2') resource that controls sorting behavior for a particular script system.

sort key: Data associated with a file that can be used to determine display order in a browser list. Sort keys commonly include filename, date, and kind

See also: sort order

sort order: Determines whether files in a browser list will be displayed in ascending or descending order

See also: sort key

sound: Anything perceived by the organs of hearing

See also: frequency, pitch, stereo sound, timbre

sound channel: A path that sound data traverses from an application to the sound output device. A sound channel is associated with a queue of sound commands and with other information about the audio characteristics of the sound data

See also: sound channel record

sound channel record: A structure that represents a sound channel. Defined by the SndChannel data type.

sound channel status record: A structure whose address you pass to the SndChannelStatus function. Defined by the SCStatus data type.

sound command: An instruction to produce sound, modify sound, or otherwise assist in the overall process of sound production

See also: sound command record

sound command record: A structure that describes a sound command. Defined by the SndCommand data type.

sound component: A component that works with the Sound Manager to manipulate audio data or to communicate with a sound output device

See also: audio component, sound output device component, utility component

sound component chain: A chain of sound components that links a sound source to a sound output device.

sound component data record: A structure that specifies information about the data stream generated by a sound component. Defined by the SoundComponentData data type.

sound component information selector: A value of type OSType that indicates the kind of information a sound component should return or modify.

Sound control panel: A control panel that allows the user to specify basic sound-related settings and preferences

See also: Alert Sounds control panel, Sound In control panel, Sound Out control panel, Volumes control panel

sound data

See: sampled-sound data, sound, square-wave data, wave-table data

sound double buffer header record: A structure that you use to manage your own double-buffering scheme. Defined by the SndDoubleBufferHeader and SndDoubleBufferHeader2 data types.

sound double buffer record: A structure that you use to manage your own double-buffering scheme. Defined by the SndDoubleBuffer data type.

Sound Driver: A device driver on the original Macintosh computers that provided sound generation. The Sound Driver is now obsolete; it has been replaced by the Sound Manager.

sound file: A file of file type 'AIFF' or 'AIFC' that can be used to store sampled-sound data and information about that data

See also: chunk, Finder sound file, sound resource

sound header: A data structure (usually stored in a sound resource) that contains information about a buffer of sampled-sound data

See also: compressed sound header, extended sound header, sampled sound header

sound information list: A structure that specifies the information associated with a sound component information selector. Defined by the SoundInfoList data type.

sound input device: Any hardware device (such as a microphone or audio digitizer) that records sound.

sound input device driver: A standard Macintosh device driver used by the Sound Manager to manage communication between applications and a sound input device.

sound input device information selector: A variable of type OSType that is used to specify the type of information that an application or the Sound Input Manager is requesting from a sound input device driver.

Sound Input Manager: The part of the Macintosh system software that controls the recording of sound from sound input devices.

sound input parameter block: A parameter block that contains information about sound recording. Defined by the SPB data type.

Sound In control panel: A subpanel of the Sound control panel that allows the user to select a sound input device

See also: Alert Sounds control panel, Sound Out control panel, Volumes control panel

Sound Manager: The part of the Macintosh system software that manages the production and manipulation of sounds on Macintosh computers.

Sound Manager status record: A structure filled in by the SndManagerStatus function, which gives information on the current CPU loading caused by all open channels of sound. Defined by the SMStatus data type.

sound output device: Any hardware device (such as a speaker or sound synthesizer) that produces sound.

sound output device component: A sound component that communicates with a sound output device

See also: utility component

Sound Out control panel: A subpanel of the Sound control panel that allows the user to select a sound output device

See also: Alert Sounds control panel, Sound In control panel, Volumes control panel

sound parameter block: A parameter block that describes the source data to be modified or sent to a sound output device. Defined by the SoundParamBlock data type.

sound recording dialog box: The dialog box displayed by the Sound Input Manager when you call SndRecord or SndRecordToFile.

sound resource: A resource of resource type 'snd ' that can be use to store sound commands and sound data

See also: sound file

sound resource header: The portion of a sound resource that describes the format of the sound resource.

sound source: The origin of a specific channel of sound.

source

See: sound source

source application: The application that sends a particular Apple event to another application or to itself. Typically, an Apple event client sends an Apple event requesting a service from an Apple event server; in this case, the client is the source application for the Apple event. The Apple event server may return a different Apple event as a reply; in this case, the server is the source for the reply Apple event.

source color: The color of a shape or pixel that is to be drawn

See also: destination color, result color

source color limits: In a transfer mode, limits on the permissible values for source color to use in transfer-mode calculations

See also: destination color limits, result color limits

source component: The sound component that provides input for a particular component.

source data: Statements in a scripting language that constitute an uncompiled script.

source ID: A unique 4-byte identifier created by the Apple Mixer to refer to a single chain of sound components linking a sound source to the current sound output device. Defined by the SoundSource data type.

source mask: A value that specifies which of a script system's subscripts the TransliterateText function is to operate on.

source matrix: A 5 X 4 matrix, part of the transfer mode structure, that allows you to manipulate the components of the source color.

source mode: A specification of which Boolean operation QuickDraw should perform when copying images or text into bitmaps or pixel maps

See also: pattern mode

source profile: The profile that is associated with the image and describes the characteristics of the device on which the image was created.

source text: A stored sequence of character codes that represents a line of text. Characters in source text are stored in input order

See also: display order, display text, input order

SP

See: stack pointer (SP)

spatial compression: Image compression that is performed within the context of a single frame. This compression technique takes advantage of redundancy in the image to reduce the amount of data required to accurately represent the image

See also: temporal compression

special handler dispatch table: A table in either the application heap or the system heap that the Apple Event Manager uses to keep track of various specialized handlers.

specific identity: A number used as shorthand for the name and key of an alternate user on a computer to provide access to a specific catalog or mail service

See also: local identity

specific object validation: A QuickDraw GX validation level that confirms that all references to a specific object type are valid.

speech: The process or product of speaking

See also: sound, synthesized speech

speech amplitude

See: speech volume

speech attribute: A setting defined for a voice or a class of voices that affects the quality of speech generated by the Speech Manager. Speech attributes include speech pitch, speech rate, pitch modulation, speech volume.

speech channel: The data structure used by the Speech Manager to store settings related to speech generation. All speech must be generated through a speech channel. Defined by the SpeechChannel data type.

speech channel control flags: Constants that enable special Speech Manager features associated with speech generation.

speech command

See: embedded speech command

speech error information record: A structure that contains information about which Speech Manager errors occurred while processing a text buffer on a given speech channel. Defined by the SpeechErrorInfo data type.

speech extension data record: A structure passed to GetSpeechInfo or SetSpeechInfo to get or set synthesizer information. Defined by the SpeechXtndData data type.

speech information selector: A variable of type OSType that is used to specify the type of information that an application or the Speech Manager is requesting from a speech synthesizer.

Speech Manager: The part of the Macintosh system software that provides a standardized method for Macintosh applications to generate synthesized speech.

speech modulation

See: pitch modulation

speech pitch: A fixed-point value on a scale from 0.000 to 100.000 that indicates the average (or baseline) frequency a speech synthesizer should use in generating synthesized speech. A value of 60.000 corresponds to Middle C on a conventional piano keyboard

See also: pitch modulation

speech rate: A fixed-point value specifying the approximate number of words per minute that a speech synthesizer should use in generating speech.

speech status information record: A structure that contains information about the status of a speech channel. Defined by the SpeechStatusInfo data type.

speech synthesizer: The executable code that is linked to a speech channel and manages all communication between the Speech Manager and the Sound Manager.

speech version information record: A structure that contains information about the speech synthesizer currently being used. Defined by the SpeechVersionInfo data type.

speech volume: A fixed-point value on a scale from 0.000 to 1.000 that indicates the average amplitude a speech synthesizer should use in generating synthesized speech. A value of 0.000 corresponds to the lowest possible volume, and a value of 1.000 corresponds to the highest.

speech-done callback procedure: An application-defined procedure that is executed when the Speech Manager completes speaking a buffer of input text.

SPI

See: system programming interface (SPI)

split caret

See: dual caret

split trap: A system software routine that is implemented as 680x0 code in ROM and as PowerPC code in an import library. Because the PowerPC code is contained directly in the import library, you cannot patch the PowerPC portion of a split trap

See also: fat trap

spool: To flatten a QuickDraw GX shape or collection of shapes and save it to a print file in preparation for printing

See also: despool

spooling phase: In QuickDraw GX printing, the phase when the application sends the document pages to disk, in preparation for printing. The printer driver stores printable output in a file from which it is subsequently despooled, rendered, and sent to the output device

See also: despooling

spool block: A data structure used in conjunction with a spool function for flattening and unflattening QuickDraw GX objects.

spool file: A temporary disk file used by an application to store data; generally used to save memory.

spool function: An application-supplied function that uses a spool block to accept flattened data from QuickDraw GX or prepare flattened data for unflattening into objects.

spool printing

See: deferred printing

square-wave data: Any set of values that represent a sound by its frequency, amplitude, and duration.

sResource: A data structure in the firmware of an expansion card's declaration ROM that defines a function or capability of the card. An sResource is also called a slot resource; the small s indicates a slot resource as opposed to the type of resource associated with the Resource Manager. There is one board sResource that identifies the card, and a functional sResource for each function a card can perform.

sResource directory: An element in a card's declaration ROM that lists all the sResources and provides an offset to each one.

sResource ID: A field in the sResource directory that identifies the type of sResource contained in or pointed to by the offset field.

SRQ

See: service request signal (SRQ)

SRT

See: slot resource table (SRT)

stack: An area of memory in the application partition that is used for temporary storage of data during the operation of that application or other software.

stack frame: The area of the stack used by a routine for its parameters, return address, local variables, and temporary storage.

stack pointer (SP): A pointer to the top of the stack

stack-based routine: A routine that receives its parameters and returns its results, if any, on the stack

See also: register-based routine

stake: An edge offset in the source text that marks the point at which a line break would be most efficient in terms of layout processing.

stale data: Data in the microprocessor's data cache whose corresponding value in RAM has changed. You might need to flush the data cache to avoid using stale data.

stale instruction: An instruction in the microprocessor's instruction cache whose corresponding values in RAM have changed. You might need to flush the instruction cache to avoid using stale instructions.

Standard Apple Numerics Environment (SANE): The floating-point environment on 680x0-based Macintosh computers and on Apple II computers. This environment provides floating-point data types and arithmetic operations, plus some advanced numerical functions (such as logarithmic and trigonometric functions)

See also: PowerPC Numerics

standard cap: A type of cap. Standard caps are square caps and semicircular caps.

Standard Catalog Package: The part of the Mac OS that manages find and browse panels for AOCE catalogs.

standard content

See: standard interchange format

standard control definition functions: Three control definition functions, stored as 'CDEF' resources in the System file. The 'CDEF' resource with resource ID 0 defines the look and behavior of buttons, checkboxes, and radio buttons; the 'CDEF' resource with resource ID 1 defines the look and behavior of scroll bars; and the 'CDEF' resource with resource ID 63 defines the look and behavior of pop-up menus.

standard date-time value: A 32-bit long integer that represents date and time purely in seconds. The standard date-time value can track dates and times only between midnight on January 1, 1904 and 6:28:15 A.M. on February 6, 2040.

standard device driver: A device driver built into the Macintosh ROM or Operating System.

Standard File Package: The part of system software that allows you to present the standard user interface when a file is to be saved or opened.

standard image-compression dialog component: A component that provides a consistent user interface for selecting parameters that govern compression of an image or image sequence and then manages the compression operation.

standard interchange format: A set of data formats that consists of plain text, styled text, sound (AIFF), images (PICT), and QuickTime movies ('MooV').

standard join: A type of join. Standard joins are sharp joins and curve joins.

Standard Mail Package: The part of the Mac OS that manages mailers and makes it easy for applications to create and send letters.

standard mode: A mode of operation available to server MSAMs and to personal MSAMs that deal with non-letter messages. An MSAM operating in standard mode hands off an incoming message to an AOCE system. It is the AOCE system, not the MSAM operating in standard mode, that is responsible for delivering the message to the ultimate destination.

Standard Roman character set: The 256 characters and character codes that are supplied with the Macintosh Roman script system. The Standard Roman character set consists of the Macintosh character set plus additional defined characters with character codes between $D9 and $FF.

standard slot space: The upper one-sixteenth of the total address space. These addresses are in the form $Fsxx xxxx, where s is a slot ID and x is any hexadecimal digit. This address space is geographically divided among the NuBus slots according to slot ID number

See also: super slot space

standard state: The size and location that an application deems the most convenient for a window.

stand-alone attribute: A record that contains only one attribute, extracted from another record. Although technically a record, the AOCE software treats a stand-alone attribute like an attribute in most circumstances. The record type of a stand-alone attribute begins with the value of the constant kAttributeValueRecTypeBody.

stand-alone code: A type of program used to supplement the standard features provided by the Mac OS , to execute startup functions, or to control peripherals. This term generally refers to classic 68K programs.

Startup Items folder: A directory located in the System Folder for storing applications and desk accessories that the user wants started up every time the Finder starts up.

startup screen: The screen on which the 'happy Macintosh' icon appears. By default, the menu bar appears on the startup screen

See also: main screen

Start Manager: A collection of routines that let you get and set system startup information located in parameter RAM.

state dependence: A condition in which a response to a request is dependent on a previous request.

statically assigned socket: One of the two classes of sockets that DDP maintains. To use a statically assigned socket, an application must request a specific socket number. Statically assigned sockets have numbers in the range of 1_127

See also: dynamically assigned socket

static data: The variables and other data that persist between calls to a particular function or fragment.

static library: A library whose code is included in the application at link time.

static text field: A control that displays static (unchangeable by the user) text labels in a window

See also: editable text field

static window: A window that doesn't change its title or reposition any of the objects within its content area.

stationery pad: A document that a user creates to serve as a template for other documents. The Finder tags a document as a stationery pad by setting the isStationery bit in the Finder flags fie ld of the file's file information record. An application that is asked to open a stationery pad should copy the template's contents into a new document and open the document in an untitled window.

status phase: The phase in which a SCSI target sends 1 byte of status information to the initiator.

status routine: (1) A device driver routine used to return status information from a driver. The function of the status routine is driver-specific. This routine is optional and need not be implemented. (2) An application-defined routine that can update windows, check the results of the low-level calls made by the Data Access Manager DBStartQuery and DBGetQueryResults functions, and cancel execution of these functions when appropriate to do so.

stereo sound: Sound that simultaneously consists of two or more channels. Also called polyphonic sound or multichannel sound

sticky: Used to describe a condition in which a bit stays set until it is explicitly cleared. Floating-point exception flags in the FPSCR are sticky, so if one instruction sets an exception flag and another instruction is performed before the flag is tested, it is impossible to tell which instruction caused the exception.

sticky error: One of two error values maintained by the Movie Toolbox. The sticky error is updated only when an application directs the Movie Toolbox to do so. The other error value, the current error, is updated by every Movie Toolbox function.

sticky menu: A menu which will remain open after the mouse button is released or the pointer is no longer on the menu.

stop alert: An alert box that informs the user of a problem or situation so serious that the user's desired action cannot be completed. Stop alerts typically have only a single button (OK), because all the user can do is acknowledge that the action cannot be completed. A stop alert is identified by an icon of an upraised hand in the upper-left corner of the alert box

See also: caution alert, note alert

storage order: The order in which character codes are stored in memory

See also: display order, input order, source text

storage reference: A specification of the storage type used to store a font

See also: storage type

storage type: The method used to store a font in a font object

See also: storage reference

storage warning: A QuickDraw GX warning indicating a data stream problem.

store-and-forward gateway: A link between different messaging systems, sometimes bridging different physical media, providing temporary data storage, and, where necessary, address translation.

store-and-forward messaging: A method of delivering messages that provides for temporary storage and forwarding of a message from one location to another, sometimes through several intermediate store-and-forward gateways or servers.

store-and-forward server: A server that provides store-and-forward messaging services. PowerShare servers are store-and-forward servers.

straight caret: A caret that is perpendicular to the baseline of the display text, regardless of the angle of the glyphs making up the text

See also: angled caret

strategy: \xE6A set of rules, such as the FTP protocol, for sending and receiving data.

stream format: The public format available for describing flattened QuickDraw GX objects. Objects in stream format are compressed or flattened. Flattened objects are unflattened when they are converted back to object format. A flattened object may be interpreted by using QuickDraw GX unflattening functions or reconstructed by parsing with an interpreter that uses the stream format.

string-manipulation resource: An international resource of type 'itl2'. The string-manipulation resource defines conventions for comparing text elements, including sorting order, character types, case conversion, and word breaks. Each installed script system has one or more string-manipulation resources.

strip an address: To clear the high-order byte of a 24-bit address, making it usable in 32-bit mode.

strong type: A glyph directionality that is always left to right or right to left

See also: neutral type, weak type

structure region: The entire area occupied by a window, including both the window frame and the content region

See also: content region, frame

structure validation: A QuickDraw GX validation level that confirms that references to object types are valid and that the properties of the object are valid

See also: all object validation, type validation

stub definition function: Code that dispatches to a definition function contained elsewhere

See also: definition function

stub definition resource: An executable resource that contains a stub definition function

See also: definition resource

stub library: A library that contains symbol definitions but no code

See also: definition stub library

style: (1) A visual attribute, other than size, applied as a systematic variation to the plain (unstyled) characteristics of a font's glyphs. The set of styles supported by QuickDraw consists of bold, italic, underline, outline, shadow, condense, and extend

See also: style object

styled text: Text that is displayed in multiple styles.

style attributes: A property of a style object. Style attributes are a set of flags that influence how the information in a style object affects a shape.

style code: A byte-length mask with one bit set for each QuickDraw-supported style to be applied.

style dialog box: A dialog box"usually displayed by an application in response to the user choosing the Page Setup command"allowing the user to specify printing options (such as the paper size and the printing orientation) that an application needs to format the document.

style object: A QuickDraw GX object associated with a shape object. A style object contains information that affects the visual appearance of a shape when it is drawn.

style property: One of the pieces of information stored in a style object and maintained by QuickDraw GX.

style reference: A reference to a style object.

style run: A sequence of text that is contiguous in memory and in which all the characters are in the same font, size, style, color, and script system.

style scrap: A TextEdit scrap that stores style information associated with text that is cut or copied.

subclass: An object class that inherits properties, element classes, and Apple events from another object class"its superclass. A subclass can also include properties, element classes, or Apple events that are not inherited from its superclass. Every object class, with the exception of cObject, is a subclass of another object class

See also: object class, superclass

subclassing: In object-oriented programming, the derivation of a new class from any existing class by adding to or overriding selected data structures and methods defined by the original class

See also: inheritance

subdirectory: A directory that is contained in some other directory. All directories on a volume except the root directory are subdirectories.

sublist: A list of attributes that appears as a distinct subset of the items displayed in an information page window, or a list of records that appears in a dNode window.

submenu: A menu that is attached to another menu.

submenu: A menu that is attached to another menu

See also: hierarchical menu

subnetwork access protocol (SNAP): An 802.2 packet header field that is used to discriminate for which protocol family a packet with a DSAP of $AA is intended.

subnormal number: A denormalized number.

subroutine linkage: The mechanism by which one routine calls another, possibly passing arguments and receiving a function result.

subscribe: To obtain data that a publisher makes available in an edition. A user subscribes to a publisher by choosing Subscribe To from the Edit menu and selecting the desired edition

See also: edition, publish

subscriber: A portion of a document that automatically obtains current data from other documents and applications. A subscriber reads data from an edition

See also: edition, section

subscript: A distinguishable subset of characters included within a script"for example, Japanese Hiragana, Katakana, Kanji, and Romaji.

subtractive color theory: The process of combining subtractive colorants such as inks or dyes. In this theory colorants of cyan, magenta, and yellow are used to subtract a portion of the white light that is illuminating an object.

suite: In the Apple Event Registry: Standard Suites, a group of definitions for Apple events, object classes, primitive object classes, descriptor types, and constants that are all used for a set of related activities. For example, the Text suite includes definitions of Apple events, object classes, and so on that are used for text processing.

superclass: The object class from which a subclass inherits properties, elements, and Apple events

See also: object class, subclass

superuser: A user who is considered to be very knowledgeable. A monitors extension can define controls that it displays for superusers only.

super slot space: The portion of memory in the range $9000 0000 through $EFFF FFFF. NuBus addresses of the form $sxxx xxxx address the super slot space that belongs to the card in slot s, where s is a slot ID and x is any hexadecimal digit

See also: standard slot space

suspend event: An event indicating that an application is about to be switched into the background and can no longer interact with the user

See also: resume event

swash: A variation of an existing glyph (often ornamental) that is noncontextual

See also: smart swash

switch

See: major switch, minor switch, mode switch

switch frame: A stack frame, created by the Mixed Mode Manager during a mode switch, that contains information about the routine to be executed, the state of various registers, and the address of the previous frame.

syllabic writing system: The glyphs that symbolize syllables in a language

See also: alphabetic writing system, ideographic writing system

symbol: A name for a discrete element of code or data in a fragment.

symmetric: Used to describe a function whose graph looks the same on both sides of the y-axis; that is, func(x) = func(_x) for all x.

symmetrical session: A session in which both ends of the connection have equal control over the communication. Both ends can send and receive data at the same time and initiate or terminate the session. A symmetrical session is also referred to as a peer-to-peer session.

symmetric multiprocessor (SMP): Having several processors in an environment where each processor executes its own tasks and its own copy of the operating system and communicates with the other processors as needed

synchronization callback procedure: An application-defined procedure that is executed whenever the Speech Manager encounters an embedded synchronization speech command in a buffer of input text.

synchronous device driver: A device driver that completes each request before returning control to the Device Manager. This type of device driver has no provision for background processing.

synchronous execution: A mode of executing a routine in which the routine is executed as soon as possible and the calling program is prevented from doing any other processing until the routine completes execution.

synchronous sound play: A playing of sound by the Sound Manager that prevents other code from executing until the sound is done playing

See also: asynchronous sound play

sync sample: A sample that does not rely on preceding frames for content

See also: key frame

synonym: A particular kind of tag object, used by QuickDraw GX to provide an alternate representation of an object for printing. The synonym specifies data, such as alternative PostScript operators, for the printer driver to use instead of the instructions that QuickDraw GX generates.

synthesized speech: The product of converting nonaural tokens (such as written or digitally-stored words or phonemes) into speech

See also: Speech Manager

synthesizer

See: speech synthesizer

synthetic font: A font created by the Font Manager from a bitmapped font resource by expanding the 1-bit font into a font that matches the current screen depth.

system alert sound

See: alert sound

system Apple event dispatch table

See: Apple event dispatch table

system coercion dispatch table

See: coercion handler dispatch table

system direction: The horizontal placement of interface elements, including the default line direction (left-to-right or right-to-left) for text in the system script. System direction is specified by the global variable SysDirection.

system environment record: A description of the operating environment filled in by the SysEnvirons function and defined by the SysEnvRec data type.

system error: An error generated by the Operating System.

system error alert box: An alert box displayed by the System Error Handler when a system error has occurred.

system error alert table resource: A resource that determines the appearance and function of system error alert boxes and system startup alert boxes.

System Error Handler: The part of the Operating System that displays an alert box when an system error occurs and manages display of the 'Welcome to Macintosh' alert box at system startup time.

system error ID: An ID number that may appear in a system error alert box to identify the error.

system extension: A file (with the file type 'INIT') containing a code resource of type 'INIT' and additional other resources. A system extension typically contains code that performs a system-level service and code that loads this system-level service into the system at system startup time.

System file: A file, located in the System Folder, that contains the basic system software plus some system resources, such as sound and keyboard resources.The System file behaves like a folder in this regard: although it looks like a suitcase icon, double-clicking it opens a window that reveals movable resource files (such as sounds, keyboard layouts, and script system resource collections) stored in the System file.

System Folder: A directory containing the software that Macintosh computers use to start up. The System Folder includes a set of folders for storing related files, such as preferences files that an application might need when starting up.

system font: The font used to display text in menus, dialog boxes, alert boxes, and so forth in a given script system. For example, in the Roman script system, the system font is Chicago.

system global variables: A collection of global variables stored in the system partition.

system heap: An area of memory in the system partition reserved for use by the Operating System.

system heap zone: The heap zone provided by the Memory Manager for use by the Operating System; equivalent to the system heap.

system initialization: The process when the system initialization code located in ROM is executed. Memory is tested and initialized, ROM drivers are installed, device drivers are located, and more.

system object accessor dispatch table

See: object accessor dispatch table

system partition: A partition of memory reserved for use by the Operating System.

system profile: The profile that defines the color characteristics for the system's display device. The ColorSync Manager provides a control panel to allow the user to specify the system profile for the current display device.

system programming interface (SPI): The programming interface to any parts of the Macintosh system software that are private to Apple Computer, Inc

system resource: A resource in the system resource file.

system result handler: A result handler that is available to all applications that use the system

See also: application result handler

system script: The primary script system used by various parts of the Operating System, such as in dialog boxes and menu bars. The system script affects system defaults, such as the system font, line direction, and text-formatting rules. All other scripts are secondary to the system script. The system script is specified in the system software's configuration resource ('itlc').

system startup: The process when the system startup code located in ROM is executed. Memory is tested and initialized, ROM drivers are installed, device drivers are located, and more.

system startup alert box: The alert box displayed at system startup time. It contains the startup greeting 'Welcome to Macintosh.'

system startup information: Certain configurable system parameters and machine-language instructions that are stored in the boot blocks of a volume and read in at system startup.

system-based VBL task: A VBL task that is not linked to an external video monitor.

Syst_me Electronique Couleur avec M_moire (SECAM): Sequential Color With Memory; refers to a color-encoding system in which the red and blue color-difference information is transmitted on alternate lines, requiring a one-line memory in order to decode green information.

s-video: A video format in which color and brightness information are encoded as separate signals. The s-video format is component video as opposed to composite video, which is the NTSC standard.