G'day ox1d0,

Welcome to the monastery.

You need some basic debugging here.

If

system ("su -l - $user -c \'$action > DBlist.txt && cat DBlist.txt\'")
+;

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doesn't work, but

system ("su -l - MyRealuser -c \'$action > DBlist.txt && cat DBlist.tx
+t\'");

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does work, then the only difference between them is $user and MyRealuser.

Use a print statement like this: 

print ">>>$user<<<\n";

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Do you get:

>>>some_username<<<

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or:

>>>some_username
<<<

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If the former, replace MyRealuser with some_username (in the system() command that worked), and see if it still works. If not, see system to learn about checking for errors. Maybe there's a problem with some_username's account or privileges.

If the latter, the newline after $user may be the culprit. You can fix that with: 

chomp(my $user = $line);

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I also note that you're using the same $line variable when reading from the EXEC and $cmd filehandles. Unless there's some specific reason for doing this, I'd use different variables, e.g. 

while(my $exec_line = <EXEC>) {
    ...
    while (my $cmd_line = <$cmd>) {
        ...
    }
}

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Even if using the same variable isn't causing any problems now, it could well turn into a hard-to-track-down bug in the future following some (seemingly innocuous) modification.

-- Ken

In reply to Re: run shell command as another user by kcott
in thread run shell command as another user by ox1d0

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