Open file for update : Open file « File « Perl






  1. Perl
  2. File
  3. Open file

Open file for update

    

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

use Fcntl qw(:seek :flock);

open LOGFILE, ">>", "/tmp/mylog" or die "Unable to open: $! \n";

# lock file for exclusive access
flock LOGFILE, LOCK_EX;

# now seek to end of file explicitly, in case it changed since the open
seek LOGFILE, 0, SEEK_END;

# write our log message
print LOGFILE "Log message...\n";

# remove lock and close file
flock LOGFILE, LOCK_UN;
close LOGFILE;








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