Problem executing Unix script from Java...

Question

Hi there, I'm having trouble executing a unix script from a java program. The script receives multiple parameters and it seems that one of them ( or more ) is not well interpreted. When I run the script directly from a shell, the script executes without any errors. But, when I run the exact same script with the exact same parameters, it does not work.
Here is the command to execute the script with all the parameters that is executed from the shell ( with success ) and also from the java program ( with errors ):
/z/opus/dcap/intfu001.csh 'NODEBUG^NOTKPROF^NOSTACK' opus dcap JACQUES JACQUES '2625781' 'ORA$PIPE$001D00D70001' JOB^DEBUG^SINISIMU^STATPROD^DECTIDANC^81^503^4080^86^87^151^97^98^99 BUT^N^N^SPRI^0^13^24^3^J^05^N^19^19^19 >> /tmp/switcher8.999.null.pgm.test
And here is my portion of code that executes the script:
Runtime wShell = Runtime.getRuntime();
Process wProc = wShell.exec(cmd_unix_final);
wProc.waitFor();
return wProc.exitValue();
Please give me your thoughts on this!
Thanks in advance!

Answer 1

Ok.
Let's proceed surgically, else we'll never solve or overcome anything.
In the last your reply you wrote:
the normal output is what I get when the script runs successfully, the script first prints a few things
and then does stuff that takes at least 2 or 3 secondsWhat do you mean?
-Finally have you got your script correctly executed?
The stuffs you spoke of are really performed?
If this is the case I can't see the prob.
Is your concern only about exitValue() for it doesn't let you distinguish programmatically
the success or failure of the script execution?
Of course you surely already have a routine in your java code to handle
exceptional situations of errors from the script.
And the "normal output" is just what you must parse to detect those errors.
Then who cares about exitValue() in this case?
Don't invoke it, relay on the stdout and stderr of the script.
-Or you get only a deceiving standard output
that let you think the script execution went alright, while instead it didn't.
In this case we have to investigate some other thing.
I can't still exclude that the problem isn't related with the buffer size of the stdout
allocated by the environment to the subprocess. You spoke of few things printed out.
Be explicit. What's the size of the output you get?
And is the "normal output" complete till the very last char
or is it truncated from somewhere on?
Also it's important that you hit a ps command after the java main process terminates
(or simply when waitFor() returns) and see if the script subprocess hung up.
As an alternative approach directly call your pro*C code from Java through JNI, instead of translating it.
1. Exec.java
public class Exec{
     static{
          System.loadLibrary("Exec");
     public static native void proCFunct();
     public static void main( String[] args){
          proCFunct();
}2. javac Exec.java
3. javah Exec
4.Exec.c
#include "Exec.h"
JNIEXPORT void JNICALL Java_Exec_proCFunct(JNIEnv * a, jclass b){
     //here call the function that executes the script
5. cc -G -I$JAVA_HOME/include -I$JAVA_HOME/include/solaris -I$YOUR_INCLUDES Exec.c -o libExec.so
6. setenv LD_LIBRARY_PATH .
7. java Exec