util/copy-if-different.pl

   1 #!/usr/local/bin/perl
   2
   3 use strict;
   4
   5 use Fcntl;
   6
   7 # copy-if-different.pl
   8
   9 # Copy to the destination if the source is not the same as it.
  10
  11 my @filelist;
  12
  13 foreach my $arg (@ARGV) {
  14         $arg =~ s|\\|/|g;       # compensate for bug/feature in cygwin glob...
  15         $arg = qq("$arg") if ($arg =~ /\s/);    # compensate for bug in 5.10...
  16         foreach (glob $arg)
  17                 {
  18                 push @filelist, $_;
  19                 }
  20 }
  21
  22 my $fnum = @filelist;
  23
  24 if ($fnum <= 1)
  25         {
  26         die "Need at least two filenames";
  27         }
  28
  29 my $dest = pop @filelist;
  30
  31 if ($fnum > 2 && ! -d $dest)
  32         {
  33         die "Destination must be a directory";
  34         }
  35
  36 foreach (@filelist)
  37         {
  38         my $dfile;
  39         if (-d $dest)
  40                 {
  41                 $dfile = $_;
  42                 $dfile =~ s|^.*[/\\]([^/\\]*)$|$1|;
  43                 $dfile = "$dest/$dfile";
  44                 }
  45         else
  46                 {
  47                 $dfile = $dest;
  48                 }
  49
  50         my $buf;
  51         if (-f $dfile)
  52                 {
  53                 sysopen(IN, $_, O_RDONLY|O_BINARY) || die "Can't Open $_";
  54                 sysopen(OUT, $dfile, O_RDONLY|O_BINARY)
  55                   || die "Can't Open $dfile";
  56                 while (sysread IN, $buf, 10240)
  57                         {
  58                         my $b2;
  59                         goto copy if !sysread(OUT, $b2, 10240) || $buf ne $b2;
  60                         }
  61                 goto copy if sysread(OUT, $buf, 1);
  62                 close(IN);
  63                 close(OUT);
  64                 print "NOT copying: $_ to $dfile\n";
  65                 next;
  66                 }
  67       copy:
  68         sysopen(IN, $_, O_RDONLY|O_BINARY) || die "Can't Open $_";
  69         sysopen(OUT, $dfile, O_WRONLY|O_CREAT|O_TRUNC|O_BINARY)
  70                                         || die "Can't Open $dfile";
  71         while (sysread IN, $buf, 10240)
  72                 {
  73                 syswrite(OUT, $buf, length($buf));
  74                 }
  75         close(IN);
  76         close(OUT);
  77         print "Copying: $_ to $dfile\n";
  78         }
  79