Help need on perl scripting

[manoj_pu]

Hello

Can any tell me how to execute two unix commands by using perl "exec()" function.

I want to execute below two commands in one shot.
1st Command is
DISPLAY=`/usr/bin/hostname`:10.0; export DISPLAY

2nd command is
/usr/bin/X11/mwm -display :10.0

Thanks & Regards
Manoj

[Rodney Hills · Accepted solution]

In perl it would be very similiar-

$display=`/usr/bin/hostname` . ":10.0";
system("DISPLAY='$display' ; /usr/bin/X11/mwm -display:10.0");

HTH

-- Rod Hills

[A. Clay Stephenson]

This is not a valid use of the exec() function in Perl. Just like its C system call counterpart, exec() replaces the currently executing process and never returns so only the first exec() will ever be executed. You need to use the system() function instead which forks a child process to execute the command.

[Simon Hargrave]

If you mean you want to run them one after the other but in one call to exec, then just chain them (like you have already chained DISPLAY= and export in the 1st "command"):

exec 'DISPLAY=`/usr/bin/hostname`:10.0; export DISPLAY ; /usr/bin/X11/mwm -display :10.0'

If you want to run them independantly in parallel, then there's no point. All your 1st command does is export a variable. Why do this if you're not going to use it, it'll disappear when you exit the exec anyhow.

[Simon Hargrave]

Of course Rodney and Clay are correct in that you should use system() not exec()!

[manoj_pu]

Thanks Everyone for the quick help.


Warm regards,

Manoj

[H.Merijn Brand (procura]

And perl promotes the %ENV hash

use Sys::Hostname;
$ENV{DISPLAY}=hostname.":10.0";
system("/usr/bin/X11/mwm");

Enjoy, Have FUN! H.Merijn