NAME
ACE_Dirent - Define a portable UNIX directory-entry iterator.
SYNOPSIS
#include <ace/Dirent.h>
class ACE_Dirent
{
public:
ACE_Dirent (void);
ACE_Dirent (const char *dirname);
int open (const char *filename);
~ACE_Dirent (void);
void close (void);
dirent *read (void);
int read (struct dirent *entry, struct dirent **result);
long tell (void);
void seek (long loc);
void rewind (void);
private:
DIR *dirp_;
};
DESCRIPTION
Define a portable directory-entry manipulation interface.
Initialization and termination methods.
ACE_Dirent (void);
Default constructor.
ACE_Dirent (const char *dirname);
Constructor calls opendir
int open (const char *filename);
Opens the directory named by filename and associates a directory stream with it.
~ACE_Dirent (void);
Destructor calls closedir.
void close (void);
Closes the directory stream and frees the DIR structure.
Iterator methods.
dirent *read (void);
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 directory stream at the next entry, except on read-only filesystems. It returns a NULL pointer upon reaching the end of the directory stream, or upon detecting an invalid location in the directory. readdir shall not return directory entries containing empty names. It is unspecified whether entries are returned for dot or dot-dot. The pointer returned by readdir points to data that may be overwritten by another call to readdir on the same directory stream. This data shall not be overwritten by another call to readdir on a different directory stream. readdir may buffer several directory entries per actual read operation; readdir marks for update the st_atime field of the directory each time the directory is actually read.
int read (struct dirent *entry, struct dirent **result);
Has the equivalent functionality as readdir except that an entry and result buffer must be supplied by the caller to store the result.
Manipulators.
long tell (void);
Returns the current location associated with the directory stream.
void seek (long loc);
Sets the position of the next readdir operation on the directory stream. The new position reverts to the position associated with the directory stream at the time the telldir operation that provides loc was performed. Values returned by telldir are good only for the lifetime of the DIR pointer from which they are derived. If the directory is closed and then reopened, the telldir value may be invalidated due to undetected directory compaction. It is safe to use a previous telldir value immediately after a call to opendir and before any calls to readdir.
void rewind (void);
Resets the position of the directory stream to the beginning of the directory. It also causes the directory stream to refer to the current state of the corresponding directory, as a call to opendir would.
AUTHOR
Douglas C. Schmidt [email protected]
LIBRARY
ace