Using Automator to run ActivePerl?

Question

(It was suggested that I post this here. Previously posted under Leopard/Automator. Note: I also considered trying to run my program at boot using launchd, but was intimidated by the sample scripts I saw. If someone can shovel me that code, I'd be grateful, but otherwise I'll keep trying to utilize the far simpler Automator application. --Peter)
Hi all,
I'm new to Mac OS and, well, a bit lost.
I've been running ActivePerl (a perl interpretor) from a Terminal prompt, passing in my program source file as an argument, as follows:
perl <path>/program_file
Program_file opens a GUI and waits for user input (ie, it does not terminate on its own). Until the user terminates this GUI (terminating ActivePerl as well), I note that a Terminal-looking icon appears on the Dock. All well and fine.
Now I'd like to have Automator run program_file at boot.
Running an Automator bash shell script with the same single line, Automator gave me a less-than-helpful message: "The action 'Run Shell Script' encountered an error. Check the action's properties and try running the workflow again."
So I figured I'd instead simply run an Automator perl shell script with the single line:
print system ("<path>/perl", "<path>/program_file");
A bit more successful, I believe this at least attempts to start ActivePerl and run program_file (a Terminal-looking icon briefly flashes on the Dock). But my GUI does not open -- program_file along with ActivePerl seem to have been terminated.
(Automator returns 512 to the print call. I can't locate a description for "512" in Mac OS X Reference Library's "Shell Scripting Primer" -- if this is where I should be looking and if this return code is even significant.)
This ought to be a very simple task. What am I missing here?
Sincere thanks.
Peter

Answer 1

(Automator returns 512 to the print call. I can't locate a description for "512" in Mac OS X Reference Library's "Shell Scripting Primer" -- if this is where I should be looking and if this return code is even significant.)
This is most likely
#define ENOENT 2 /* No such file or directory */
I could be wrong, so take this with a grain of salt.
One form of program completion status is formatted as
8bits 8bits
| | |
| errno | signal |
|_______|_______|
0000:0010:0000:0000
So if my guess is correct, then 512 is breaks down into a value of 2 in the errno byte and a value of 0 in the signal byte.
This also makes sense in that it is unlikely an Automator run would get a signal, and it is not unusual for someone to assume that the PATH used by their Terminal session is the same everywhere, and that is often NOT true, so commands your Terminal finds are not always findable by Automator, Launchd, cron, Applescript, etc...
For example, while you might specify the full path to your perl script, that does not mean that any commands run inside the perl script will find their commands.
You say ActivePerl. Well is that a special version of Perl? Where is it located? Does it have any special features that are NOT part of the default Perl?
I do have -- as far as I understand these things -- $PATH set correctly in my home directory's .profile file. I'll check this Friday, too.
Having the correct PATH set for your Terminal session means nothing to Automator. If you have things in your perl script that depend on a custom PATH, then you are in trouble.
You might want to create an experimental Automator that is "Run Shell Script". Change the "cat" command to:
printenv
Run this workflow in Automator. Click on the "Results". You will most likely see
SHELL=/bin/bash
TMPDIR=/var/folders/zv/zvU6bMiHTeElG+JIWOdzk++TI/-Tmp-/
ApplePubSub_SocketRender=/tmp/launch-s1i3Ke/Render
USER=harris
COMMAND_MODE=unix2003
SSHAUTHSOCK=/tmp/launch-6mdwXe/Listeners
_CF_USER_TEXTENCODING=0x1F5:0:0
PATH=/usr/bin:/bin:/usr/sbin:/sbin
PWD=/Users/yourusername
DBUSLAUNCHD_SESSION_BUS_SOCKET=/tmp/launch-V5WJ8H/unix_domainlistener
SHLVL=1
HOME=/Users/yourusername
LOGNAME=yourusername
DISPLAY=/tmp/launch-Pq6WiM/:0
_=/usr/bin/printenv
Notice that PATH is "/usr/bin:/bin:/usr/sbin:/sbin". That is it. If your Perl script cannot find everything it needs in one of those directories, then you are going to have to either arrange your Perl script to provide full paths to anything it needs outside of PATH, or you are going to have to modify your Automator workflow so it sets up a PATH that makes your Perl script happy. For exampe you could setup your "Run Shell Script" something like:
export PATH="$PATH:/your/custom/path:/another/custom/path"
/path/to/your/desired/version/of/perl /path/to/your/perl/script
Maybe this won't be as simple as I thought it should be. (Laugh or sigh at me, but I like Windows because I don't need to deal with this sort of thing! Stuff just happens by itself. No, I should not entertain programming as a profession.)
Changing environments is always difficult because you keep trying to do thing the old way, because that is what you know. This is a natural situation.
So maybe if you actually told us what you really trying to do, someone can suggest an easier way to do what you want. You have only told us your solution, and not what you want to do.
We know you want to prompt for something, and you want to do this at boot time. We don't know why you want to do this, or what this GUI is displaying, what action you want the user (you) to do with this GUI display. Again, maybe there is another way to do what you want which is more Mac like and easier.