SCANDIR(3)
NAME
scandir − scan a directory
USAGE
#include <sys/types.h>
#include <sys/dir.h>
scandir(dirname, namelist, select, compar)
char *dirname;
struct direct *(*namelist[]);
int (*select)();
int (*compar)();
alphasort(d1, d2)
struct direct **d1, **d2;
DESCRIPTION
Scandir 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 and a pointer to the array through namelist.
The select parameter is a pointer to a user-supplied subroutine that scandir calls to select which entries will 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 that is passed to qsort(3) 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.
The memory allocated for the array can be deallocated with free (see malloc(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.