NAME
scandir, alphasort - scan a directory for matching entries
SYNOPSIS
#include <dirent.h>
int scandir(const char *dir, struct dirent ***namelist,
int (*select))(const struct dirent *),
int (*compar))(const struct dirent **, const struct dirent **));
int alphasort(const struct dirent **a, const struct dirent **b);
DESCRIPTION
The scandir() function scans the directory dir, calling
select() on each directory entry. Entries for which
select() returns non-zero are stored in strings allocated
via malloc(), sorted using qsort() with the comparison func-
tion compar(), and collected in array namelist which is
allocated via malloc(). If select is NULL, all entries are
selected.
The alphasort() function can be used as the comparison func-
tion for the scandir() function to sort the directory
entries into alphabetical order. Its parameters are the two
directory entries, a and b, to compare.
RETURN VALUE
The scandir() function returns the number of directory
entries selected or -1 if an error occurs.
The alphasort() function returns an integer less than, equal
to, or greater than zero if the first argument is considered
to be respectively less than, equal to, or greater than the
second.
ERRORS
ENOMEM
Insufficient memory to complete the operation.
CONFORMING TO
BSD 4.3
EXAMPLE
/* print files in current directory in reverse order */
#include <dirent.h>
main(){
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);
}
SEE ALSO
opendir(3), readdir(3), closedir(3), rewinddir(3),
telldir(3), seekdir(3).