perl function chdir

In Perl, the chdir function is used to change the current working directory. It takes a single argument, which is the path to the new working directory.

Here's an example that demonstrates the use of the chdir function:

use strict;
use warnings;

# get the current working directory
my $cwd = `pwd`;
print "Current directory: $cwd\n";

# change the working directory
chdir('/tmp');

# get the new working directory
$cwd = `pwd`;
print "New directory: $cwd\n";

In the above example, we first use backticks to execute the pwd command and get the current working directory. We then print this directory to the screen.

We then use the chdir function to change the working directory to /tmp. We use backticks again to execute the pwd command and get the new working directory, which we print to the screen.

When run, the above example will output something like the following:

Current directory: /home/user
New directory: /tmp

This indicates that the working directory was successfully changed from /home/user to /tmp.

Note that the chdir function can also be used with a block, which temporarily changes the working directory only for the duration of the block. For example:

use strict;
use warnings;

{
    # change the working directory temporarily
    local $ENV{PWD} = '/tmp';
    chdir;

    # current working directory is now /tmp
    my $cwd = `pwd`;
    print "Temporary directory: $cwd\n";
}

# current working directory is back to its original value
my $cwd = `pwd`;
print "Current directory: $cwd\n";

In this example, we use the local keyword to create a local copy of the PWD environment variable and set it to /tmp. We then call the chdir function without any arguments, which changes the working directory to /tmp. We use backticks again to execute the pwd command and get the new working directory, which we print to the screen.

After the block, the working directory is changed back to its original value, which we again print to the screen.