io::dirent(3pm) [debian man page]
Dirent(3pm) User Contributed Perl Documentation Dirent(3pm) NAME
IO::Dirent - Access to dirent structs returned by readdir SYNOPSIS
use IO::Dirent; ## slurp-style opendir DIR, "/usr/local/foo"; my @entries = readdirent(DIR); closedir DIR; print $entries[0]->{name}, " "; print $entries[0]->{type}, " "; print $entries[0]->{inode}, " "; ## using the enumerator opendir DIR, "/etc"; while( my $entry = nextdirent(DIR) ) { print $entry->{name} . " "; } closedir DIR; DESCRIPTION
readdirent returns a list of hashrefs. Each hashref contains the name of the directory entry, its inode for the filesystem it resides on and its type (if available). If the file type or inode are not available, it won't be there! nextdirent returns the next dirent as a hashref, allowing you to iterate over directory entries one by one. This may be helpful in low- memory situations or where you have enormous directories. IO::Dirent exports the following symbols by default: readdirent nextdirent The following tags may be exported to your namespace: ALL which includes readdirent, nextdirent and the following symbols: DT_UNKNOWN DT_FIFO DT_CHR DT_DIR DT_BLK DT_REG DT_LNK DT_SOCK DT_WHT These symbols can be used to test the file type returned by readdirent in the following manner: for my $entry ( readdirent(DIR) ) { next unless $entry->{'type'} == DT_LNK; print $entry->{'name'} . " is a symbolic link. "; } For platforms that do not implement file type in its dirent struct, readdirent will return a hashref with a single key/value of 'name' and the filename (effectively the same as readdir). This is subject to change, if I can implement some of the to do items below. CAVEATS
This was written on FreeBSD and OS X which implement a robust (but somewhat non-standard) dirent struct and which includes a file type entry. I have plans to make this module more portable and useful by doing a stat on each directory entry to find the file type and inode number when the dirent.h does not implement it otherwise. Improvements and additional ports are welcome. TO DO
o For platforms that do not implement a dirent struct with file type, do a stat on the entry and populate the structure anyway. o Do some memory profiling (I'm not sure if I have any leaks or not). COPYRIGHT
Copyright 2002, 2011 Scott Wiersdorf. This library is free software; you can redistribute it and/or modify it under the terms of the Perl Artistic License. AUTHOR
Scott Wiersdorf, <scott@perlcode.org> ACKNOWLEDGEMENTS
Thanks to Nick Ing-Simmons for his help on the perl-xs mailing list. SEE ALSO
dirent(5), perlxstut, perlxs, perlguts, perlapi COPYRIGHT AND LICENSE
Copyright (C) 2007 by Scott Wiersdorf This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.1 or, at your option, any later version of Perl 5 you may have available. perl v5.14.2 2011-08-22 Dirent(3pm)
Check Out this Related Man Page
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