Hi Joyce & Michael:
> I also tried this (on behalf of Joyce on behalf of me) with Java 6 and see the same behavior. Permissions are still set as -rwxrwxr-x
This suggests that the process using 'creat()' to create a file has supplied a 'mode' argument of '0777' when you use a umask of '0002'.
Two things come into play when a file is created. First, when a 'creat()' system call is performed, the code has the option of specifying an octal permissions value. The shell uses 666 for files. Whatever value is supplied, though, is subject to the application of the 'umaask' of the process. Hence if the 'umask' is 022 and the default permissions for the 'create()' are 666, the "subtraction" of the two means that the created file will have permissions of 644. With a creation mask of 666 and a 'umask' of 000, the file has permissions of 666.
If the code performing the file creation uses a creation mask of 644 (instead of 666), then even with a 'umask' of 000, a resulting file will have permissions of 644.
Hence, the creating code has the "upper limit" of the least restrictive permissions that will apply.
You can evaluate this behavior with this small Perl script:
# cat ./mymodes
#!/usr/bin/perl
use strict;
use Fcntl;
my $file = '/tmp/myfile';
unlink $file;
sysopen( FH, $file, O_CREAT, 0777 ) or die "Error: $!\n";
print "$file created\n";
Regards!
...JRF...
