Oh Wise Monks,

A need recently arose to pipe an arbitrary (short) string into a shell command and get the results. I wanted to avoid open2, and thought: the biggest issue is that some malicious person might try to inject things like "$" and quote characters, etc. No problem: I can write something that converts my input string into something that the Unix command printf (or echo -e) will interpret into the correct string, which then gets piped to the command. But then it didn't work: 

$cmd = "printf 'I\\x27ll'"; print $cmd . "\n"; print `$cmd` ."\n";

[download]

printf 'I\x27ll'
I\x27ll

I am confused because the shell gives the result I want, but backticks (and open '-|') do not!

> printf 'I\x27ll'
I'll Help??

In reply to backslashes in shell commands by Anonymous Monk

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