Your own error message is from your shell

/sbin/sh:
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That's the program that produced the error message. Perl never sees the argument. The part before the ":" in your error message is always the calling program. If Perl was having a problem you would see 'perl' or '/usr/bin/perl' or somesuch there.

You need this:

#perl multi.pl "a b ccc-ddd_eee\
> fff:ggg.hhh iii(jjj)lllll"
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Or

#perl multi.pl a\ b\ ccc-ddd_eee\\\n\ fff:ggg.hhh\ iii\(jjj\)lllll
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Note that I escaped the spaces too as I assume you want to pass your program just one argument, while the spaces create multiple arguments.

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