Some Perl lines won't execute from Java Runtime.getRuntime().exec() -

i have strange behavior when calling perl script java.

the perl code is:

#!/usr/bin/env perl use warnings;  print "dada\n"; $file = "settings.txt"; open $ds, "<", $file; print "doudou\n";  while ($line = <$ds>){     print "$line\n";     last if $. == 4; }  print "dodo\n"; close $ds; 

as can see, in code want read file "settings.txt" contents :

1 : 2 : b 3 : c 4 : d 

and script works when called cygwin , output :

dada doudou 1 : 2 : b 3 : c 4 : d dodo 

but when call java using following code:

string line; string cmd = "perl c:\\data\\tests\\match_settings.pl";  try {     process proc = runtime.getruntime().exec(cmd);     bufferedreader in = new bufferedreader(new inputstreamreader(proc.getinputstream()));     while ((line = in.readline()) != null) {         system.out.println("line :" + line);     }     in.close(); } catch (ioexception a) {     // todo auto-generated catch block     a.printstacktrace(); } 

then when java function executed, output:

line :dada line :doudou line :dodo 

which means $line = <$ds> not executed, don't know why.

any idea ?

sorry long post, wanted precise possible.

ps : know of wondering "why not read settings.txt file java code himself ?" that's not question here ;)

it seems folder perl code executed not same when executing cygwin , java. perl script can't find file.

you should add error checking in perl code, , verify current working dir directory.

i write:

#!/usr/bin/env perl use warnings; use cwd;  $cwd = cwd();      print "dada\n"; print "in folder: $cwd"; $file = "settings.txt"; open ($ds, "<", $file) || die "can't open settings.txt. error code: $!"; print "doudou\n";  while ($line = <$ds>){     print "$line\n";     last if $. == 4; }  print "dodo\n"; close $ds; 

this debug why, when script executed java, don't expected results.

you should redirect stderr stdout in java code, error lines.