However the backticks don't like that

Really? Works for me.

$ perl -e'print `echo foo \\
bar`'
foo bar
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$ cat foo.pl
print ` echo foo \\
bar`;
$ perl foo.pl
foo bar
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That's curious, becouse I can do command line splitting with "\" in my shell.
And here backticks are not working:


$ cat backticks.pl                              
#!/usr/bin/perl
`ls \
-l *.pl`;
$ perl backticks.pl                             
sh: line 1: -l: command not found
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Backticks interpolate, so you have to escape your \ character: thus \\. String interpolation.

You're not passing a slash to the shell. Backticks are like "". If you want the resulting string to contain a slash, you need to escape it.

$ perl -le'print "foo
bar"'
foo
bar

$ perl -le'print "foo\
bar"'
foo
bar

$ perl -le'print "foo\\
bar"'
foo\
bar
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You can also use a HEREDOC but interpolation still occurs so the backslash needs escaping.

$ cat > testfile
line 1
line 2
line 3
line 4
line 5
$ perl -e '
> $result = <<`EOC`;
> tail -2 \\
> testfile
> EOC
> print $result;'
line 4
line 5
$
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I hope this is of interest.

Cheers,

JohnGG

Since backticks interpolate variables, one straight-forward solution would be to store your desired system command in a string and then execute it. Perhaps something like this:

my $string = 'This will all be ';
$string   .= 'one string.';
`$string`;
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You could also use the system command, which would let you split your command and arguments into terms in an array, which is then passed to the OS. You should also take a look at exec. Missed the return string requirement - sorry.

Backticks capture output, but system doesn't. Using exec directly is too much work. open '|-' would be the appropriate choice here.

$ perl -e'
>    my @cmd = ( echo => "foo\nbar" );
>    open(my $fh, "|-", @cmd);
>    print <$fh>;
> '
foo
bar
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Bonus: The shell isn't involved if the command has an argument.

When I have situations like this, that I want to run various bash commands, I start questioning if my perl calling bash, shouldn't be turned into bash calling perl.

When I get here, I want to step back, break down my perl into smaller scripts, and use bash creatively to call them up.