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From: PerlFAQ Server on 25 Jul 2010 18:00
This is an excerpt from the latest version perlfaq3.pod, which
comes with the standard Perl distribution. These postings aim to
reduce the number of repeated questions as well as allow the community
to review and update the answers. The latest version of the complete
perlfaq is at http://faq.perl.org .

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3.24: Why don't Perl one-liners work on my DOS/Mac/VMS system?

The problem is usually that the command interpreters on those systems
have rather different ideas about quoting than the Unix shells under
which the one-liners were created. On some systems, you may have to
change single-quotes to double ones, which you must *NOT* do on Unix or
Plan9 systems. You might also have to change a single % to a %%.

For example:

# Unix (including Mac OS X)
perl -e 'print "Hello world\n"'

# DOS, etc.
perl -e "print \"Hello world\n\""

# Mac Classic
print "Hello world\n"
(then Run "Myscript" or Shift-Command-R)

# MPW
perl -e 'print "Hello world\n"'

# VMS
perl -e "print ""Hello world\n"""

The problem is that none of these examples are reliable: they depend on
the command interpreter. Under Unix, the first two often work. Under
DOS, it's entirely possible that neither works. If 4DOS was the command
shell, you'd probably have better luck like this:

perl -e "print <Ctrl-x>"Hello world\n<Ctrl-x>""

Under the Mac, it depends which environment you are using. The MacPerl
shell, or MPW, is much like Unix shells in its support for several
quoting variants, except that it makes free use of the Mac's non-ASCII
characters as control characters.

Using qq(), q(), and qx(), instead of "double quotes", 'single quotes',
and `backticks`, may make one-liners easier to write.

There is no general solution to all of this. It is a mess.

[Some of this answer was contributed by Kenneth Albanowski.]



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are not necessarily experts in every domain where Perl might show up,
so please include as much information as possible and relevant in any
corrections. The perlfaq-workers also don't have access to every
operating system or platform, so please include relevant details for
corrections to examples that do not work on particular platforms.
Working code is greatly appreciated.

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