director(3) [minix man page]

DIRECTORY(3)						     Library Functions Manual						      DIRECTORY(3)

NAME

       directory, opendir, readdir, rewinddir, closedir, telldir, seekdir - directory routines

SYNOPSIS

       #include <sys/types.h>
       #include <dirent.h>

       DIR *opendir(const char *dirname)
       struct dirent *readdir(DIR *dirp)
       void rewinddir(DIR *dirp)
       int closedir(DIR *dirp)

       #define _MINIX  1
       #include <sys/types.h>
       #include <dirent.h>

       long telldir(DIR *dirp)
       int seekdir(DIR *dirp, long pos)

DESCRIPTION

       These routines form a system independent interface to access directories.

       Opendir() opens the directory dirname and returns a pointer to this open directory stream.

       Readdir()  reads  one  entry  from  the directory as a pointer to a structure containing the field d_name, a character array containing the
       null-terminated name of the entry.

       Rewinddir() allows the directory to be read again from the beginning.

       Closedir() closes the directory and releases administrative data.

       The Minix specific functions telldir() and seekdir() allow one to get the current position in the directory file and to return there later.
       Seekdir() may only be called with a position returned by telldir() or 0 (rewind).  These functions should not be used in portable programs.

SEE ALSO

       dir(5).

DIAGNOSTICS

       Opendir() returns a null pointer if dirname can't be opened, or if it can't allocate enough memory for the DIR structure.

       Readdir() returns null if there are no more directory entries or on error.

       Closedir() and seekdir() returns 0 on success, -1 on error.

       Telldir() returns -1 on error.

       All  of	them  set errno appropriately.	Readdir() will only set errno on error, not on end-of-dir, so you should set errno to zero before-
       hand, and check its value if readdir() returns null.

NOTES

       The return value of readdir() needs to be copied before the next operation on the same directory if it is to be saved.

AUTHOR

       Kees J. Bot (kjb@cs.vu.nl)

																      DIRECTORY(3)

DIRECTORY(3)						   BSD Library Functions Manual 					      DIRECTORY(3)

NAME

     closedir, dirfd, opendir, readdir, readdir_r, rewinddir, seekdir, telldir -- directory operations

LIBRARY

     Standard C Library (libc, -lc)

SYNOPSIS

     #include <dirent.h>

     int
     closedir(DIR *dirp);

     int
     dirfd(DIR *dirp);

     DIR *
     opendir(const char *dirname);

     struct dirent *
     readdir(DIR *dirp);

     int
     readdir_r(DIR *restrict dirp, struct dirent *restrict entry, struct dirent **restrict result);

     void
     rewinddir(DIR *dirp);

     void
     seekdir(DIR *dirp, long loc);

     long
     telldir(DIR *dirp);

DESCRIPTION

     The opendir() function opens the directory named by dirname, associates a directory stream with it, and returns a pointer to be used to iden-
     tify the directory stream in subsequent operations.  The pointer NULL is returned if dirname cannot be accessed or if it cannot malloc(3)
     enough memory to hold the whole thing.

     The readdir() function returns a pointer to the next directory entry.  It returns NULL upon reaching the end of the directory or detecting an
     invalid seekdir() operation.

     readdir_r() provides the same functionality as readdir(), but the caller must provide a directory entry buffer to store the results in.  If
     the read succeeds, result is pointed at the entry; upon reaching the end of the directory, result is set to NULL.	readdir_r() returns 0 on
     success or an error number to indicate failure.

     The telldir() function returns the current location associated with the named directory stream.  Values returned by telldir() are good only
     for the lifetime of the DIR pointer (e.g., dirp) from which they are derived.  If the directory is closed and then reopened, prior values
     returned by telldir() will no longer be valid.

     The seekdir() function sets the position of the next readdir() operation on the directory stream.	The new position reverts to the one asso-
     ciated with the directory stream when the telldir() operation was performed.

     The rewinddir() function resets the position of the named directory stream to the beginning of the directory.

     The closedir() function closes the named directory stream and frees the structure associated with the dirp pointer, returning 0 on success.
     On failure, -1 is returned and the global variable errno is set to indicate the error.

     The dirfd() function returns the integer file descriptor associated with the named directory stream, see open(2).

     Sample code which searches a directory for entry ``name'' is:

	   len = strlen(name);
	   dirp = opendir(".");
	   while ((dp = readdir(dirp)) != NULL)
		   if (dp->d_namlen == len && !strcmp(dp->d_name, name)) {
			   (void)closedir(dirp);
			   return FOUND;
		   }
	   (void)closedir(dirp);
	   return NOT_FOUND;

LEGACY SYNOPSIS

     #include <sys/types.h>
     #include <dirent.h>

     <sys/types.h> is necessary for these functions.

SEE ALSO

     close(2), lseek(2), open(2), read(2), compat(5), dir(5)

HISTORY

     The closedir(), dirfd(), opendir(), readdir(), rewinddir(), seekdir(), and telldir() functions appeared in 4.2BSD.

BSD
								   June 4, 1993 							       BSD