how to capture PID for a child script Post: 302333781

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Top Forums Shell Programming and Scripting how to capture PID for a child script Post 302333781 by aman jain on Tuesday 14th of July 2009 04:41:01 AM

07-14-2009

Registered User

how to capture PID for a child script

Thanks for the information about trap command. I'm stuck in a specific situation here. I have a code snippet.

Code:

#!/bin/ksh
set -vx
PID=$$
echo "parent PID =$$"
echo "calling process1"
. $TEMP_DIR/file5
stat=$?
echo $stat
echo "calling process2"
. $TEMP_DIR/file6 &
PID2=$!
export PID2
echo "PID2= $PID2"
echo "PID1= $PID"
wait "$PID2"
status=$?
echo $status
if [ "$status" = "0"  ];then
        echo "file1 successful"
else
        echo "file1 failed"
       ## exit 1;
fi

if [ $stat -eq 0 ];then
        echo "file2 successful"
else
        echo "file2 failed"
        ##exit 1;
fi

This code is capturing the exit status of both the processes ; one in forground and other in background. Now , when i change the code to

Code:

#!/bin/ksh
set -vx
PID=$$
echo "parent PID =$$"
echo "calling process1"
. $TEMP_DIR/file5 &
PID2=$!
export PID2

echo "calling process2"
. $TEMP_DIR/file6 
status=$?
echo $status
 
echo "PID2= $PID2"
echo "PID1= $PID1"
if [ "$status" = "0"  ];then
        echo "file1 successful"
else
        echo "file1 failed"
        exit 1;
fi
wait "$PID2"
stat=$?
echo $stat
if [ $stat -eq 0 ];then
        echo "file2 successful"
else
        echo "file2 failed"
        exit 1;
fi

then the process just exists after process 2 and does not return the exit codes for either of the processes. Any idea why it is happening?

Last edited by Yogesh Sawant; 07-14-2009 at 05:58 AM.. Reason: added code tags

aman jain

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LEARN ABOUT SUNOS

echo

echo(3XCURSES)						  X/Open Curses Library Functions					    echo(3XCURSES)

NAME

       echo, noecho - enable/disable terminal echo

SYNOPSIS

       cc [ flag... ] file... -I /usr/xpg4/include -L /usr/xpg4/lib 
       -R /usr/xpg4/lib -lcurses [ library... ]

       c89 [ flag... ] file... -lcurses [ library... ]

       #include <curses.h>

       int echo(void);

       int noecho(void);

DESCRIPTION

       The  echo()  function enables Echo mode for the current screen. The noecho() function disables Echo mode for the current screen. Initially,
       curses software echo mode is enabled and hardware echo mode of the tty driver is disabled. The echo() and noecho() functions control  soft-
       ware echo only. Hardware echo must remain disabled for the duration of the application, else the behavior is undefined.

RETURN VALUES

       Upon successful completion, these functions return OK. Otherwise, they return ERR.

ERRORS

       No errors are defined.

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Standard			   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |Unsafe			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       getch(3XCURSES), getstr(3XCURSES), initscr(3XCURSES), libcurses(3XCURSES), scanw(3XCURSES), attributes(5), standards(5)

SunOS 5.10							    5 Jun 2002							    echo(3XCURSES)

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