perl program to handle return of batch file - perl

Question

i am trying to run a batch file from a perl script but i am not able to handle the return of a batch file. below is my code
perl script:
// call a batch file
my $output =system("D:\\WORKSPACE\\CC_Triggers\\batch_file.bat");
// based on output check the status of the batch file
if($output==0){
print "success in trigger**********";
}
else
{
print "FAilure**********";
}
batch file:
set "java_output="
setlocal enableDelayedExpansion
//this will call a java program and get return value.
for /f "delims=" %%J in ('java -cp "PMDfileRead.jar;jxl.jar" PMDfileRead') do (
set "java_output=!java_output! %%J"
)
endlocal & set java_output=%java_output%
// check the ouput of java and act accordingly
IF %java_output% == 1 (
echo failed
exit(1);
)else (
echo succeeded
)
basically i am trying to validate an xls file and return flag from java code which is being called by a batch file and from ther i need to return back to perl script which i am not able to get. in case of success and failure, i am getting as "0" as output due to which output is success.. request to please correct my code or suggest me the best way to handle this.

Answer 1

edit: Sorry i somehow read past the comment by mpapec stating the same thing.
The Perl part is fine. If you always get a 0, it has to be the batch script acting up. Or the Java.
If you want to inspect the return value in Perl for anything except whether it is zero or not, then you would have to shift it right 8 bits.
my $output = (system("D:\\WORKSPACE\\CC_Triggers\\batch_file.bat")) >> 8;
But as you only check for zero or not, that should not be an issue here.
edit:
When using Windows, it is important to never define an environment variable ERRORLEVEL as that will mix up with the actual exit codes returned by applications. This is explained in more detail here: How do I get the application exit code from a Windows command line?

Answer 2

Replace your system() call with backticks instead:
A system() wrapped call returns the exit status of the command, whereas using ``'s returns the actual STDOUT (i.e. your echo statements)
For more info:
What's the difference between Perl's backticks, system, and exec?
i.e.:
my $output = `D:\WORKSPACE\CC_Triggers\batch_file.bat`;