opendir.txt

[随书类]Dos6.0源代码

SUMMARY   methods to gain access to file system directories (OS2 1.2 only)

#include <dirent.h>

DIR *opendir(char *szDirName)

struct dirent *readdir(DIR *pd)

int closedir(DIR *pd)

void rewinddir(DIR *pd)

DESCRIPTION

  The type DIR which is defined in the header file <dirent.h> represents a 
directory stream, which is an ordered sequence of all the directory entries
in a particular directory.  Directory entries represent files; files may be 
removed from a directory or added to a directory asynchronously to the 
operations described in this section.

The opendir() function opens a directory stream corresponding to the 
directory named by the dirname argumnet.  The directory stream is positioned
at the first entry.

The readdir() function returns a pointer to a structure representing the 
directory entry at the current position in the directory stream to which dirp
refers and positions the irectory stream at the next entry.  It returns a
NULL pointer upon reaching the end of the directory stream.  The dot and
dot-dot directory entries are included in the search and returned to the 
caller.

The rewinddir() function resets the position of the directory stream to
which dirp refers to the begining of the directory.  

The closedir() function closes the directory stream referred to by dirp.

RETURN VALUE

  Upon successful completion, the readdir() function returns a pointer 
to an object of type struct dirent that includes the member: 
char[] d_name (a null terminated filename).  Otherwise, a value of NULL
is returned and errno is set to indicate the error.

  The readdir() function returns a pointer to an object of type struct dirent.
When an error is encountered, a value of NULL is returned and errno is set
to indicate the error.  When the end of the directory is encountered,
a value of NULL is returned and errno is not changed by this function call.

  Upon successfull completion, closedir() returns a value of zero.  
Otherwise a value of -1 is returned and errno is set to indicate the error.


IMPLEMENTATION

SEE ALSO   

NOTE

EXAMPLE