Consider:
#!/usr/local/bin/perl
$files = "C:\\Users\\A\\workspace\\CCoverage\\backup.txt";
unlink ($files);
open (OUTFILE, '>>$files');
print OUTFILE "Something\n";
close (OUTFILE);
The above is a simple subroutine I wrote in Perl, but it doesn't seem to work. How can I make it work?
Answer
Variables are interpolated only in strings using double quotes ". If you use single quotes ' the $ will be interpreted as a dollar.
Try with ">>$files" instead of '>>$files'
Always use
use strict;
use warnings;
It will help to get some more warnings.
In any case also declare variables
my $files = "...";
You should also check the return value of open:
open OUTFILE, ">>$files"
or die "Error opening $files: $!";
Edit: As suggested in the comments, a version with the three arguments open and a couple of other possible improvements
#!/usr/bin/perl
use strict;
use warnings;
# warn user (from perspective of caller)
use Carp;
# use nice English (or awk) names for ugly punctuation variables
use English qw(-no_match_vars);
# declare variables
my $files = 'example.txt';
# check if the file exists
if (-f $files) {
unlink $files
or croak "Cannot delete $files: $!";
}
# use a variable for the file handle
my $OUTFILE;
# use the three arguments version of open
# and check for errors
open $OUTFILE, '>>', $files
or croak "Cannot open $files: $OS_ERROR";
# you can check for errors (e.g., if after opening the disk gets full)
print { $OUTFILE } "Something\n"
or croak "Cannot write to $files: $OS_ERROR";
# check for errors
close $OUTFILE
or croak "Cannot close $files: $OS_ERROR";