Perl Exec with Spaces

nevafuse has asked for the wisdom of the Perl Monks concerning the following question:

I'm trying to launch a windows executable from a perl script.

$BaseDir = "C:\\Program Files\\myprog\\";
$cmd = $BaseDir."myprog";
`$cmd`;
[download]

The problem is that the backticks wait for the program to be exited before continuing. From my understanding the backticks are supposed to act like exec, not system.

If I do exec $cmd; then it gives me an error because of the space between Program and Files. If I try system is does the same thing the backticks do.

I even tried putting quotations around the file path before I passed it to the exec command but the perl script exits without errors after I close the executed program without finishing the rest of my script.

Comment on Perl Exec with Spaces Download Code

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Re: Perl Exec with Spaces by kyle (Abbot) on Mar 11, 2009 at 19:53 UTC
I think on Windows, what you're trying to do is best done with system. `system( 1, qq{"$cmd"} );` [download] See also launching external program with SYSTEM causes script to hang until program closed among many others.	[reply] [d/l]
Re^2: Perl Exec with Spaces by nevafuse (Novice) on Mar 11, 2009 at 19:55 UTC
Thank you, I didn't realize system would allow me to execute something without waiting for it to end.	[reply]
Re: Perl Exec with Spaces by xyzzy (Pilgrim) on Mar 11, 2009 at 19:42 UTC
windows shells don't have escape sequences for spaces, so you have to put double quotes inside $cmd. try: `$cmd = "\"$BaseDir$myprog\""` Everything is true." "Even false things?" "Even false things are true" "How can that be?" "I dunno man, I didn't do it."	[reply] [d/l]
Re^2: Perl Exec with Spaces by nevafuse (Novice) on Mar 11, 2009 at 19:47 UTC
I did, it executes the program, but exits the perl script without warning and most importantly without finishing the rest of my script.	[reply]
Re^3: Perl Exec with Spaces by ikegami (Patriarch) on Mar 11, 2009 at 19:55 UTC
As it should. You can either use IPC::Open3 or launch your application via `start`.	[reply] [d/l]
Re: Perl Exec with Spaces by VinsWorldcom (Prior) on Mar 11, 2009 at 20:03 UTC
Something I've used before in a Perl script to launch a 'tail -f' in a CMD.EXE window so I could monitor along with file output as the Perl script runs: `if (-e "c:\\usr\\bin\\tail.exe") { system ("start \"TITLE OF WINDOW - $LOG\" \"c:\\usr\\bin\\tail.exe +\" -f $LOG") }` [download] $LOG is a variable populated with the create log file that I'm tailing. 'start' is a built-in Windows command to launch a program. Note that you'll need to supply the first argument (in the above example: \"TITLE OF WINDOW - $LOG\") if you're going to use quotes or arguments to your program; otherwise, start will interpret the args wrong. For information, open CMD.EXE and do: {C} > start /?	[reply] [d/l]