SCANDIR(3C)SCANDIR(3C)NAME
scandir, scandir64, alphasort, alphasort64 - scan a directory
SYNOPSIS
SysV:
#include <sys/types.h>
#include <dirent.h>
int scandir(const char *dirname, struct dirent **namelist[],
int (*select)(struct dirent *),
int (*compar)(struct dirent **, struct dirent **));
int alphasort(struct dirent **d1, struct dirent **d2);
int scandir64(const char *dirname, struct dirent64 **namelist[],
int (*select)(struct dirent64 *),
int (*compar)(struct dirent64 **, struct dirent64 **));
int alphasort64(struct dirent64 **d1, struct dirent64 **d2);
BSD:
#include <sys/types.h>
#include <sys/dir.h>
int scandir(const char *dirname, struct direct **namelist[],
int (*select)(), int (*compar)());
int alphasort(struct direct **d1, struct direct **d2);
DESCRIPTION
The inclusion of <dirent.h> selects the System V versions of these
routines. For the 4.3BSD versions, include <sys/dir.h>.
Scandir reads the directory dirname and builds an array of pointers to
directory entries using malloc(3C). It returns the number of entries in
the array and a pointer to the array through namelist.
The select parameter 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 parameter is a pointer to a user supplied subroutine which is
passed to qsort(3C) to sort the completed array. If this pointer is null,
the array is not sorted. alphasort is a routine which can be used for
the compar parameter to sort the array alphabetically.
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SCANDIR(3C)SCANDIR(3C)
The memory allocated for the array can be deallocated with free (see
malloc(3C)) by freeing each pointer in the array and the array itself.
The scandir64 and alphasort64 interfaces differ from scandir and
alphasort, respectively, in that they use dirent64 structures instead of
dirent structures.
SEE ALSOdirectory(3C), malloc(3), qsort(3C), dirent(4)DIAGNOSTICS
Returns -1 if the directory cannot be opened for reading or if malloc(3C)
cannot allocate enough memory to hold all the data structures.
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