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From:	iunknown2k4 AT yahoo DOT co DOT in (anonymous)
Newsgroups:	comp.os.msdos.djgpp
Subject:	Problem using system( )
Date:	18 Sep 2004 03:01:51 -0700
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To:	djgpp AT delorie DOT com
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I read the documentation for the system() function and I could understand
that if the COMMAND.COM is used then it will always return 0, even if
the command did not execute.

I want to know whether the command passed to the system()
was successfully run or not. I am not able to understand
the following:
 
"The behavior of `system' can be customized at run time by defining the
variable `DJSYSFLAGS' in the environment.  The value of that variable
should be the numerical value of `__system_flags' that you'd like to
set; it will override the value of `__system_flags' specified when the
program was compiled."

Does it mean that the `DJSYSFLAGS' should be defined something like 

#define DJSYSFLAGS  (  __system_emulate_command | __system_use_shell \
                                  |__system_call_cmdproc)


Also the return value is in the lower 8 bits, 
so I'm checking it like

struct retVal
 {
  char  r[2];
 }*ret;

...

int temp = system(cmd);
ret = (struct retVal *) &temp;
printf ("\n %d %d", ret->r[0], ret->r[1]);

....

But, the vales are always zero even for system() called with
an invalid command.

Am I doing something wrong?
Please help.

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