Re: calling .EXE through Perl script

[Anonymous Monk]

Here is my script which i tried...

use strict;
use warnings;

$dir = "C:\\parser_pgm\\test";
opendir(TXT, $dir) or die "Can't open $dir: $!";
while( defined ($file = readdir TXT) ) {
`parser_pgm.exe $file`;
}
closedir(XML);

[Zaxo]

Yes, you are calling backticks in void context. You're ignoring the screen output of your program, so you have no evidence that it ran. Try this modification:

$dir = "C:\\parser_pgm\\test";
opendir(TXT, $dir) or die "Can't open $dir: $!";
while( defined ($file = readdir TXT) ) {
    print `parser_pgm.exe $file`;
}
closedir(TXT); # not XML

Is that more like what you expect?

[Thelonius]

How are you running this script? If you run it from the command line, you'll get these errors:

Global symbol "$dir" requires explicit package name at test.pl line 4.
Global symbol "$dir" requires explicit package name at test.pl line 5.
Global symbol "$dir" requires explicit package name at test.pl line 5.
Global symbol "$file" requires explicit package name at test.pl line 6
+.
Global symbol "$file" requires explicit package name at test.pl line 7
+.
Execution of test.pl aborted due to compilation errors.

If you're running the program by double-clicking on the file in Windows Explorer, you're probably not going to see the errors before the DOS box closes.

I think this code is what you want:

use strict;
use warnings;

my $dir = "C:\\parser_pgm\\test";
opendir(DIR, $dir) or die "Can't open $dir: $!";
while(my $file = readdir DIR) {
  my $pathname = "$dir\\$file";
  if (-f $pathname) {
    # I added the -f test after running this and finding
    # out that readdir returns "." and ".."
    # (At least on the version of ActivePerl I am using)

    print STDERR "running parser_pgm.exe on $pathname\n"; # for debugg
+ing


    system("parser_pgm.exe \"$pathname\"");
      # I added quotes in case there are spaces in the
      # file name (or in directory name in case you change it.

    if ($? != 0) {
      print STDERR "parser_pgm returned error $?\n";
    }
  }
}
closedir(DIR);

[Anonymous Monk]

Hi Thelonius,
Thanks a lot for your help. Indeed your code works. And as suggested by other monks I was not reading the output and hence was not aware if script really did the job.

Thanks one and all for the needful.

Regards
Ashutosh

[GrandFather]

You should skip directories. At least '.' and '..' exist.

use strict;
use warnings;

$dir = "C:\\parser_pgm\\test";
opendir(TXT, $dir) or die "Can't open $dir: $!";
while( defined ($file = readdir TXT) ) {
    next if ! -f $file; # Skip if not a file
    `parser_pgm.exe $file`;
}
closedir(TXT);

Note also that I've changed the closedir(XML); to closedir(TXT); to match the opendir. The defined check is redundant by the way.