Name: dk106046 Date: 08/19/2004

OPERATING SYSTEM(S):
LinuxIA32, All RH

FULL JDK VERSION(S):
java version "1.4.2-beta"
Java(TM) 2 Runtime Enviornment , Standard Edition (build 1.4.2-beta-b06)
Java HotSpot(TM) Client VM (build 1.4.2-beta-b06, mixed mode)

Exact steps to reproduce:

1)Create two users belonging to same primary group and secondary group
for e.g
uid=501(ben) gid=100(users) groups=100(users),101(maxwell)
uid=500(richard) gid=100(users) groups=100(users),101(maxwell)

2)Build the hello.c file and Wrapper.java file for one user.
  for e.g
  -rwxr-xr-x 1 richard users 8345 2004-08-02 23:34 hello

3)As root, change the permissions and ownership of the "C" program
  to another user
  for e.g.
  -r-xr-x--- ben:maxwell hello

4) As "richard", the program can still be run
   i.e.
    [janet:/home/richard/test]hello
    o/p--> HelloWorld

   But the Java wrapper fails to find the program
  [janet:/home/richard/test]java Wrapper
   o/p --->
    java.io.IOException: java.io.IOException: ./hello: cannot execute
    at java.lang.UNIXProcess.<init>(UNIXProcess.java:143)
    at java.lang.Runtime.execInternal(Native Method)
    at java.lang.Runtime.exec(Runtime.java:566)
    at java.lang.Runtime.exec(Runtime.java:428)
    at java.lang.Runtime.exec(Runtime.java:364)
    at java.lang.Runtime.exec(Runtime.java:326)
    at Wrapper.main(Wrapper.java:16)
  

Source code that demonstrates the problem:-
-----------------------------------------------------------------------
hello.c:

 #include <stdio.h>
 #include <stdlib.h>
 #include <stddef.h>
                                                                        
 int main( void )
 {
     printf( "HelloWorld\n" );
     system( "id -a > out.txt" );
     return 66;
 }

Wrapper.java:
import java.io.IOException;
                                                                        
public class Wrapper {
                                                                        
   public static void main(String[] args) {
                                                                        
   String program = "./hello";
   if (args.length > 0)
   {
              program = args[0];
   }
                                                                        
   Runtime r = Runtime.getRuntime();
                                                                        
   try {
           Process p = r.exec( program );
           p.waitFor();
           System.out.println( p.exitValue() );
       }
       catch (IOException e)
       {
              e.printStackTrace();
       }
       catch (InterruptedException e)
       {
              e.printStackTrace();
       }
  }
}

======================================================================