Re: A 'strange' character("^M") of contrasting color appearing unexpededly at the end of lines of a unix file. How can it be removed?

[TechFly]

I recently ran into this same issue. I wrote the following short script to fix it. I don't know if it will work with everything, but it has for everything I have given it. Just supply the info it asks for, and it will create the FIXED file for you.

#!/usr/bin/perl -w
use strict;
use warnings;

my $FILE;
my $DST;
my $filename;
print("What file do you want to remove the trailing Carrige Returns fr
+om:");
while($filename=<STDIN>){
    chomp($filename);
    last;
}
open (FILE, '<', $filename) or die "Failed to open file:$!";
open (DST, '>', "FIXED".$filename) or die "Failed to open fix file:$!"
+;
while (<FILE>){
    if($_ =~ /\r$/){
        s/\r//;    
        print DST $_;    
    }
    else{
               print DST $_;
    }
}
print("The file $filename has been fixed. The new file name is FIXED".
+$filename.".\n");
close FILE;

I am sure there are improvements that could be made, but it was a nice study on input output and basic regex.

I found that the ^M is indeed the same as a \r as is mentioned a couple of times above. This script just replaces it with nothing, essentially deleting it.

Cheers.

[AR]

You may have an intention error in your while(<FILE>) loop. Right now, you're testing if the string ends with a \r and then you're removing the first occurrence of it. If your string is "Hello \rthere\r\n", your code would print "Hello there\r\n" to DST.

If I understand your intention correctly, I would replace the while loop with the following:

while (<FILE>){
    s/\r$//;
    print DST $_;
}

If you want to get rid of all occurrences of \r in the line, you could just say:

while (<FILE>){
    s/\r//g;
    print DST $_;
}

[TechFly]

Heh, now that I look at it there, I notice that I neglected to close DST too. Oops.