Re^2: Start an MS window in background from a perl script

& is a sh thing

But, in a sense, that's an oversimplification. I mean, if I run (in Cygwin's bash shell):

Rob@desktop2 ~
$ perl -e 'system "notepad &"'
[download]

then that works as intended. But if I invoke ActivePerl (in the very same Cygwin shell) by running:

Rob@desktop2 ~
$ /cygdrive/c/_32/ap822/bin/perl -e 'system "notepad &"'
[download]

then I get the precise (undesired) behaviour as described by the op - where I get told that &.txt does not exist.

Is it simply a case of "ActivePerl always assumes that it's being run in the cmd shell" ? ... or is there a more erudite way of explaining this ?

Cheers,
Rob

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Re^3: Start an MS window in background from a perl script by ikegami (Patriarch) on Sep 19, 2007 at 14:48 UTC
There's no assumption being made as to which shell launched Perl. As documented, the shell used by `system` is constant. On most platforms, that shell is `/bin/sh` (no matter what the user's login shell is or which process launched `perl`), so `system`'s argument must be a `sh` command. `&` can be used to run a background task in `sh`. On Windows (cygwin aside), that shell is `cmd`, so `system`'s argument must be a `cmd` command. `start` can be used to run a background task in `cmd`.	[reply] [d/l] [select]

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Re^3: Start an MS window in background from a perl script
by ikegami (Patriarch) on Sep 19, 2007 at 14:48 UTC

There's no assumption being made as to which shell launched Perl. As documented, the shell used by system is constant.

On most platforms, that shell is /bin/sh (no matter what the user's login shell is or which process launched perl), so system's argument must be a sh command. & can be used to run a background task in sh.

On Windows (cygwin aside), that shell is cmd, so system's argument must be a cmd command. start can be used to run a background task in cmd.

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