In a perl script, in the top lines, where one designates the interpreter, the perl wisdom for systems where the kernel might not do the right thing with a "#!" line, is to use the form:
#!/bin/sh -- # -*- perl -*-
eval 'exec /data/local/bin/perl -S $0 ${1+"$@"}'
  if $running_under_some_script;
So, why ${1+"$@"} instead of just "$@"? I know that "$@" expands to all the arguments quoted (e.g. "$1" "$2", etc). But the other form I don't quite see. I mean, what's the 1+ do? I've searched the for the documentation on what this extra bracketed format accomplishes, and I can't find it. And surprisingly, Google can't handle that search string.

If someone knows the answer, or an online reference to this, I'd be very happy...

cheers!
-cadphile...

In reply to what's the difference between "$@" and ${1+"$@"} by cadphile

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