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SCANDIR(3)               BSD Library Functions Manual               SCANDIR(3)

NAME
     scandir, alphasort -- scan a directory

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <sys/types.h>
     #include <dirent.h>

     int
     scandir(const char *dirname, struct dirent ***namelist, int (*select)(struct dirent *),
         int (*compar)(const void *, const void *));

     int
     alphasort(const void *d1, const void *d2);

DESCRIPTION
     The scandir() function reads the directory dirname and builds an array of pointers to directory entries
     using malloc(3).  It returns the number of entries in the array.  A pointer to the array of directory
     entries is stored in the location referenced by namelist.

     The select argument is a pointer to a user supplied subroutine which is called by scandir() to select
     which entries are to be included in the array.  The select routine is passed a pointer to a directory
     entry and should return a non-zero value if the directory entry is to be included in the array.  If
     select is null, then all the directory entries will be included.

     The compar argument is a pointer to a user supplied subroutine which is passed to qsort(3) to sort the
     completed array.  If this pointer is null, the array is not sorted.

     The alphasort() function is a routine which can be used for the compar argument to sort the array
     alphabetically.

     The memory allocated for the array can be deallocated with free(3), by freeing each pointer in the
     array and then the array itself.

DIAGNOSTICS
     Returns -1 if the directory cannot be opened for reading or if malloc(3) cannot allocate enough memory
     to hold all the data structures.

SEE ALSO
     directory(3), malloc(3), qsort(3), dir(5)

HISTORY
     The scandir() and alphasort() functions appeared in 4.2BSD.

BSD                              June 4, 1993                              BSD