What does "__FD_PRN_" means in perl code ?

UNIX for Advanced & Expert Users
1

I have seen something like this in a perl code:

$_ =~ s/__FD_PRN_/\\(/g

What does this "__FD_PRN_" means. I have searched google but was not able to find any info regarding this. Appreciate if some one can refer to a link for these characters. From comments/code it used to substitue "(" with "\(".

2 
 
$ ./test.pl 
ABC\(EFG

 
$ cat test.pl
#!/usr/bin/perl
$test = "ABC__FD_PRN_EFG";
$test =~ s/__FD_PRN_/\\(/g;
print "$test\n";
3

Thanks for reply, but i am really interested in knowing significance of "__FD_PRN_". Is this a ascii or some other representation of "(" ? Could you please let me know what exactly these codes are called and is it specific to perl only?

4

It's nothing special to Perl, just a string it searches for and then replaces. The only thing it's probably specific to is the application that generated the original string.