scandir


SYNOPSIS
       #include <dirent.h>

       int scandir(const char *dirp, struct dirent ***namelist,
              int (*filter)(const struct dirent *),
              int (*compar)(const struct dirent **, const struct dirent **));

       int alphasort(const void *a, const void *b);

       int versionsort(const void *a, const void *b);

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       scandir(), alphasort(): _BSD_SOURCE || _SVID_SOURCE
       versionsort(): _GNU_SOURCE

DESCRIPTION
       The  scandir()  function  scans the directory dirp, calling filter() on
       each directory entry.  Entries for which filter() returns  nonzero  are
       stored  in  strings allocated via malloc(3), sorted using qsort(3) with
       the comparison function compar(), and collected in array namelist which
       is  allocated  via  malloc(3).   If  filter  is  NULL,  all entries are
       selected.

       The alphasort() and versionsort() functions can be used as the compari-
       son  function  compar().  The former sorts directory entries using str-
       coll(3), the latter using strverscmp(3) on the strings (*a)->d_name and
       (*b)->d_name.

RETURN VALUE
       The scandir() function returns the number of directory entries selected
       or -1 if an error occurs.

       The alphasort() and versionsort()  functions  return  an  integer  less
       than,  equal  to, or greater than zero if the first argument is consid-
       ered to be respectively less than, equal to, or greater than  the  sec-
       ond.

ERRORS
       ENOENT The path in dirp does not exist.

       ENOMEM Insufficient memory to complete the operation.

       ENOTDIR
              The path in dirp is not a directory.

VERSIONS
       versionsort() was added to glibc in version 2.1.

CONFORMING TO
       alphasort() and scandir() are specified in POSIX.1-2008, and are widely
       available.  versionsort() is a GNU extension.

       Since  glibc  2.1,  alphasort()  calls strcoll(3); earlier it used str-
       cmp(3).

EXAMPLE
       #define _SVID_SOURCE
       /* print files in current directory in reverse order */
       #include <dirent.h>

       int
       main(void)
       {
           struct dirent **namelist;
           int n;

           n = scandir(".", &namelist, 0, alphasort);
           if (n < 0)
               perror("scandir");
           else {
               while (n--) {
                   printf("%s\n", namelist[n]->d_name);
                   free(namelist[n]);
               }
               free(namelist);
           }
       }

SEE ALSO
       closedir(3),   fnmatch(3),   opendir(3),   readdir(3),    rewinddir(3),
       seekdir(3), strcmp(3), strcoll(3), strverscmp(3), telldir(3)

COLOPHON
       This  page  is  part of release 3.35 of the Linux man-pages project.  A
       description of the project, and information about reporting  bugs,  can
       be found at http://man7.org/linux/man-pages/.



GNU                               2011-09-08                        SCANDIR(3)
Man Pages Copyright Respective Owners. Site Copyright (C) 1994 - 2017 Hurricane Electric. All Rights Reserved.