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opensnoop(1m)                                   USER COMMANDS                                  opensnoop(1m)



NAME
       opensnoop - snoop file opens as they occur. Uses DTrace.

SYNOPSIS
       opensnoop [-a|-A|-ceghsvxZ] [-f pathname] [-n name] [-p PID]

DESCRIPTION
       opensnoop  tracks  file opens. As a process issues a file open, details such as UID, PID and pathname
       are printed out.

       The returned file descriptor is printed, a value of -1 indicates an error. This  can  be  useful  for
       troubleshooting to determine if appliacions are attempting to open files that do not exist.

       Since  this  uses  DTrace,  only the root user or users with the dtrace_kernel privilege can run this
       command.

OPTIONS
       -a     print all data

       -A     dump all data, space delimited

       -c     print current working directory of process

       -e     print errno value

       -g     print full command arguments

       -s     print start time, us

       -v     print start time, string

       -x     only print failed opens

       -Z     print zonename

       -f pathname
              file pathname to snoop

       -n name
              process name to snoop

       -p PID process ID to snoop


EXAMPLES
       Default output, print file opens by process as they occur,
              # opensnoop


       Print human readable timestamps,
              # opensnoop -v


       See error codes,
              # opensnoop -e


       Snoop this file only,
              # opensnoop -f /etc/passwd


FIELDS
       ZONE   Zone name

       UID    User ID

       PID    Process ID

       PPID   Parent Process ID

       FD     File Descriptor (-1 is error)

       ERR    errno value (see /usr/include/sys/errno.h)

       CWD    current working directory of process

       PATH   pathname for file open

       COMM   command name for the process

       ARGS   argument listing for the process

       TIME   timestamp for the open event, us

       STRTIME
              timestamp for the open event, string

DOCUMENTATION
       See the DTraceToolkit for further documentation under the Docs directory. The DTraceToolkit docs  may
       include full worked examples with verbose descriptions explaining the output.

EXIT
       opensnoop will run forever until Ctrl-C is hit.

BUGS
       occasionally the pathname for the file open cannot be read and the following error will be seen,

       dtrace: error on enabled probe ID 6 (...): invalid address

       this is normal behaviour.

AUTHOR
       Brendan Gregg [Sydney, Australia]

SEE ALSO
       dtrace(1M), truss(1)




version 1.60                                    Jan 12, 2006                                   opensnoop(1m)