isalive.exe

I needed to use ping in a batch file to determine if a particular host was 
'up'.  Unfortunately, the ping supplied with Novell's LAN Workplace didn't  
set a DOS errorlevel to use in a conditional in a batch file.  I didn't find a 
suitable (free) utility, so I wrote one.

Basically, it's a filter used on the output of ping that sets the DOS 
errorlevel to 0 (normal) if the pinged device is alive, or to 1 is the device 
is not alive.  It simply looks for the string 'alive' in the output of ping.


The relevent section of an autoexec.bat file:

ping hostname | isalive
if errorlevel 1 goto DEAD
rem hostname is alive, put needed lines between here and goto END

goto END
:DEAD
rem hostname is not responding, put needed lines between here and END

:END



The source code for 'isalive.c'

/* isalive.c	use with 'ping' to set DOS errorlevel to 1 if not alive
	         								 0 if alive
	Mark Gogins 2/28/93 Compuserve 70243,1412
	Please feel free to modify any and all of this as you wish, even sell
	it for big bucks if you can. This program is free, clear, and released  
	to the public domain.  The author assumes no responsibility for any 
	damage or loss caused by the use of this program, however it
	comes down.
*/

#include <stdio.h>
#include <string.h>
#include <process.h>
#include <stdlib.h>

#define DEAD 1
#define ALIVE 0

void main()
{
	char temp[128];
	gets(temp);
	if ( strstr(temp,"alive"))
    			{
    				printf(temp);
    				_exit(ALIVE);
                 }
                 else
                 {
    	             	printf(temp);
                   	_exit(DEAD);
                 }
}