How do I test the permissions of a file for user, group, and all?

[sherifradwan]

How do I test the permission of a file for user, group, and all?

Originally posted as a Categorized Question.

[chicks]

Here's a script that shows how to use stat to get what you're looking for and an example invocation.

$ cat fileperm
#!/usr/bin/perl

my $filename = 'fileperm';

my $mode = (stat $filename)[2];

$mode = $mode & 07777; # mask off file type;
my $usr = ($mode & 0700) >> 6;
my $grp = ($mode & 0070) >> 3;
my $oth = $mode & 0007;

printf "$filename has permissions %04o (%i,%i,%i)\n", $mode, $usr, $gr
+p, $oth;
$ ./fileperm
fileperm has permissions 0775 (7,7,5)
$ ls -l fileperm
-rwxrwxr-x    1 chicks   chicks        289 Apr 21 11:32 fileperm

[particle]

see stat

[ehdonhon]

print "Testing File: $test_file\n";

my ( $mode, $uid ) = (stat( $test_file ))[2,4] or die "Stat failed.\n"
+;
my ( $ownername ) = getpwuid $uid;

print "File is owned by '$ownername'\n";

my $ms = 'xwrxwrxwr';
my $modestring;

for ( 0..8 ) {
    if ( $mode & ( 2 ** $_ ) ) {
       $modestring = substr( $ms, $_ , 1 ) . $modestring;
    } else {
       $modestring = '-' . $modestring;
    }
}

print "File permissions are $modestring\n";