SCANDIR(3C) Standard C Library Functions SCANDIR(3C)
NAME
scandir, alphasort - scan a directory
SYNOPSIS
#include <sys/types.h>
#include <dirent.h>
int scandir(
const char *dirname,
struct dirent *(*
namelist[]),
int (*
select)(const struct dirent *),
int (*
dcomp)(
const struct dirent **,
const struct dirent **));
int alphasort(
const struct dirent **d1,
const struct dirent **d2);
DESCRIPTION
The
scandir() function reads the directory
dirname using
readdir(3C) and builds an array of pointers to directory entries using
malloc(3C). The
namelist argument is a pointer to an array of
structure pointers. The
select argument is a pointer to a routine
that is called with a pointer to a directory entry and returns a non-
zero value if the directory entry is included in the array. If this
pointer is
NULL, then all the directory entries are included. The
dcomp argument is a pointer to a routine that is passed to
qsort(3C),
which sorts the completed array. If this pointer is
NULL, the array
is not sorted.
The
alphasort() function can be used as the
dcomp() function
parameter for the
scandir() function to sort the directory entries
into alphabetical order, as if by the
strcoll(3C) function. Its
arguments are the two directory entries to compare.
RETURN VALUES
The
scandir() function returns the number of entries in the array and
a pointer to the array through the
namelist argument. When an error
is encountered,
scandir() returns -1 and
errno is set to indicate the
error.
The
alphasort() function returns an integer greater than, equal to,
or less than 0 if the directory entry name pointed to by
d1 is
greater than, equal to, or less than the directory entry name pointed
to by
d2 when both are interpreted as appropriate to the current
locale. There is no return value reserved to indicate an error.
ERRORS
The
scandir() function will fail if:
EOVERFLOW The number of directory entries exceeds the number that
can be represented by an
int.
USAGE
The
scandir() and
alphasort() functions have transitional interfaces
for 64-bit file offsets. See
lf64(7).
ATTRIBUTES
See
attributes(7) for descriptions of the following attributes:
+--------------------+-----------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-----------------+
|Interface Stability | Stable |
+--------------------+-----------------+
|MT-Level | See below. |
+--------------------+-----------------+
The
scandir() function is Unsafe. The
alphasort() function is Safe.
SEE ALSO
malloc(3C),
qsort(3C),
readdir(3C),
strcoll(3C),
attributes(7),
lf64(7) May 4, 2004 SCANDIR(3C)
