perl: replacing a special line in a file

markus1982 · 09-26-2002, 12:25 PM

I'm wondering if there is a easier solution to replace 1 line in a file ... this script just should change the /etc/login.defs ... any ideas?

Code:

#!/usr/bin/perl

# change min lengh of passwords
    open(FHANDLE, "/etc/login.defs");
    @file_content = <FHANDLE>;
    close(FHANDLE);
    
    for ($i = 0; $i < scalar(@file_content); $i++) {
        if (!(@file_content[$i] =~ /^#/) && (@file_content[$i] =~ /PASS_MIN_LEN/)) {
            $file_content[$i] = "PASS_MIN_LEN\t8\n";
            last; }   
    }

    open(FHANDLE, ">/etc/login.defs");
    print FHANDLE @file_content;    
    close(FHANDLE);

lackluster · 09-26-2002, 02:05 PM

I'd do this :

Code:

#!/usr/bin/perl

$input_file = "/etc/login.defs";
open(FIN, $input_file);
open(FOUT, ">$input_file");

while(<FIN>) {
   next if m/^#/;
   print FOUT "PASS_MIN_LEN\t8\n" and last if m/PASS_MIN_LEN/;
}

untested, but you get the idea.