Readers will be familiar with the idea of returning the permissions of a file using the ls -l command, which, amongst other things, returns file permission information as shown in this example:

-rwxr-xr-x *various info* someFile

Does anyone know a convenient way of returning the permissions of a file in Octal notation instead of the usual 'rwx..'?

e.g.:

755 *various info* someFile

I could use any of various filters to strip out the Octal permission from other input, but wouldn't it be nice to have a command returning JUST the Octal permission...if this is possible?

Adapt this as needed:

#! /bin/sh
FILE=/your/file

MODE=`perl -e 'printf "%04o", (stat("@ARGV"))[2] & 07777;' $FILE`

echo $MODE

-jim

Jim:

That's a good solution - definitely TOP DRAWER!

Since I'm a Perl newbie, how about an explanation of how it works? I take it 'stat' is an internal Perl function?

Regards,

Nails

Learning perl from O'reilly covers this in more detail. Basically, the stat function returns a 13-element list giving the status info for a file.

($dev,$ino,$mode,$nlink,$uid,$gid,$rdev,$size, $atime,$mtime,$ctime,$blksize,$blocks) = stat($filename);

0 - dev - device number of filesystem
1 - ino - inode number
2 - mode - file mode (type and permissions)
3 - nlink - number of (hard) links to the file
4 - uid - numeric user ID of file's owner
5 - gid - numeric group ID of file's owner
6 - rdev - the device identifier (special files only)
7 - size - total size of file, in bytes
8 - atime - last access time since the epoch
9 - mtime - last modify time since the epoch
10 - ctime - inode change time since the epoch
11 - blksize - preferred block size for file system I/O
12 - blocks - actual number of blocks allocated

Do a google/CPAN search on perl stat function for more info.

-jim

That solution works fine - nice one!