Perl file Testing

Operators and meanings of file tests in perl

Test file permissions:

-R files or directories are currently (valid) readable for users.

-W files or directories are writable to current (valid) users.

-X files or directories are executable to (valid) users currently.

-O files or directories are available to (valid) users currently.

-R files or directories are readable to actual users or groups.

-W files or directories can be written to actual users or groups.

-X files or directories can be executed by actual users or groups.

-O files or directories owned by actual users

The test file exists:

-E files or directories exist.

-Z file exists but no content

-S file or directory exists

Test file type:

-F is a common file.

-D is the Directory

-L is a symbolic link.

-S is a socket-type file.

-P is the named pipe.

-B is a block device file.

-C is a character device file.

-The setuid bit is set in the u file or directory.

-The setguid bit is set in the g file or directory.

-The sticky bit is set in the-k file or directory.

-T file handle is a TTY device

-T text file

-B: Binary File

Test file time:

-M: the number of days since the last modification

-A: the number of days since the last access

-C Number of days since the last file node was changed

The following perl program can check whether the files in a directory are readable and executable. The directory name is passed in by the command line.

#!/usr/bin/perl -wopendir(FH,"@ARGV[0]");my @list=readdir FH;closedir(FH)foreach my $file (@list){if (-r -w -x $file){print "$file is readable,writeable and excuteable\n"}}