DIRECTORY(3) DIRECTORY(3)
NAME
opendir, readdir, telldir, seekdir, closedir - directory
operations
SYNOPSIS
#include <sys/types.h>
#include <ndir.h>
DIR *opendir(filename)
char *filename;
struct direct *readdir(dirp)
DIR *dirp;
long telldir(dirp)
DIR *dirp;
seekdir(dirp, loc)
DIR *dirp;
long loc;
closedir(dirp)
DIR *dirp;
DESCRIPTION
Opendir opens the directory named by filename and associates
a `directory stream' with it. Opendir returns a pointer to
be used to identify the directory stream in subsequent oper-
ations. The pointer value 0 is returned if filename cannot
be accessed or is not a directory.
Readdir returns a pointer to the next directory entry. It
returns 0 upon reaching the end of the directory or detect-
ing an invalid seekdir operation.
Telldir returns the current location associated with the
named directory stream.
Seekdir sets the position of the next readdir operation on
the directory stream. The new position reverts to the one
associated with the directory stream when the telldir opera-
tion was performed. Values returned by telldir are good
only for the lifetime of the DIR pointer from which they are
derived.
Closedir causes the named directory stream to be closed, and
the structure associated with the DIR pointer to be freed.
struct direct {
u_long d_ino; inode for the entry
DIRECTORY(3) DIRECTORY(3)
short d_reclen; don't use
short d_namlen; equivalent to strlen(d_name)
char d_name[MAXNAMLEN+1]; null-terminated entry name
};
The preferred way to search the current directory is:
DIR *dirp;
dirp = opendir(".");
for(dp = readdir(dirp); dp != 0; dp = readdir(dir))
if(strcmp(dp->d_name, name) == 0)
break;
closedir(dirp);
/* found name if dp != 0 */
SEE ALSO
dir(5), open(2), dirread(2), read(2), lseek(2), ftw(3)
BUGS
The return values point to static data whose content is
overwritten by each call.