NAME

File::Stat::Bits - stat(2) bit mask constants

SYNOPSIS

            

              
              
use File::stat;
use File::Stat::Bits;
my $st = stat($file) or die "Can't stat $file: $!";
if ( S_ISCHR($st->mode) ) {
my ($major, $minor) = dev_split( $st->rdev );
print "$file is character device $major:$minor\n";
}
printf "Permissions are %04o\n", $st->mode & ALLPERMS;
            
          

(Too many S_IF* constants to example)

DESCRIPTION

Lots of Perl modules use the Unix file permissions and type bits directly in binary form with risk of non-portability for some exotic bits. Note that the POSIX module does not provides all needed constants and I can't wait when the POSIX module will be updated.

This separate module provides file type/mode bit and more constants from sys/stat.ph and sys/sysmacros.ph without pollution caller's namespace by other unneeded symbols from these headers. Most of these constants exported by this module are Constant Functions (see perlsub).

Since some of Perl builds does not include these converted headers, the build procedure will generate it for itself in the its own lib directory.

This module also should concentrate all portability and compatibility issues.

CONSTANTS

File type bit masks (for the st_mode field):

            

              
              
S_IFMT          bitmask for the file type bitfields
S_IFDIR directory
S_IFCHR character device
S_IFBLK block device
S_IFREG regular file
S_IFIFO fifo (named pipe)
S_IFLNK symbolic link
S_IFSOCK        socket
            
          

File access permission bit masks (for the st_mode field):

            

              
              
S_IRWXU mask for file owner permissions
S_IRUSR owner has read permission
S_IWUSR owner has write permission
S_IXUSR owner has execute permission
S_ISUID set UID bit
S_IRWXG mask for group permissions
S_IRGRP group has read permission
S_IWGRP group has write permission
S_IXGRP group has execute permission
S_ISGID set GID bit
S_IRWXO mask for permissions for others
S_IROTH others have read permission
S_IWOTH others have write permisson
S_IXOTH others have execute permission
S_ISVTX sticky bit
            
          

Common mode bit masks:

            

              
              
ACCESSPERMS      0777
   ALLPERMS     07777
DEFFILEMODE      0666
            
          

FUNCTIONS

File type test macros (for the st_mode field):

            

              
              
S_ISDIR ( mode )        directory?
S_ISCHR ( mode )        character device?
S_ISBLK ( mode )        block device?
S_ISREG ( mode )        regular file?
S_ISFIFO( mode )        fifo (named pipe)?
S_ISLNK ( mode )        is it a symbolic link?
S_ISSOCK( mode )        socket?
            
          

All returns boolean value.

$major = major( $st_rdev )

Returns major device number of st_rdev

$minor = minor( $st_rdev )

Returns minor device number of st_rdev

($major, $minor) = dev_split( $st_rdev )

Splits st_rdev to major and minor device numbers

$st_rdev = dev_join( $major, $minor )

Makes st_rdev from major and minor device numbers (makedev())

NOTE

If major/minor definitions absent in reasonable set of system C headers all major/minor related functions returns undef.

SEE ALSO

stat(2)

File::stat(3)

AUTHOR

Dmitry Fedorov <dm.fedorov@gmail.com>

COPYRIGHT

Copyright (C) 2003 Dmitry Fedorov <dm.fedorov@gmail.com>

LICENSE

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

DISCLAIMER

The author disclaims any responsibility for any mangling of your system etc, that this script may cause.

cpanm File::Stat::Bits

perl -MCPAN -e shell
install File::Stat::Bits