learn_gnuawk

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Hi, in the regular expressions chapter, I found an inaccuracy related to escaping characters in the incoming input.

Matching the metacharacters

$ echo '\learn\by\example' | awk '{gsub(/\\/, "/")} 1'
/learn/by/example

Using string literal as a regexp

# another example
$ echo '\learn\by\example' | awk '{gsub("\\\\", "/")} 1'
/learn/by/example
$ echo '\learn\by\example' | awk '{gsub(/\\/, "/")} 1'
/learn/by/example

In these examples, we don't escape the incoming text '\learn\\by\\example' with extra slashes and so echo returns the wrong string \learyample on pipe for awk.