Re: The awk bug

[John Cowan]

Kaplenko Vitaliy scripsit:

> $ echo "./some_script" | awk 'gsub(".","a") {print $0}'
> aaaaaaaaaaaaa
> 
> But must be:
> 
> $ echo "./some_script" | awk 'gsub(".","a") {print $0}'
> a/some_script

Not so.  The first argument of gsub is interpreted as a regular
expression, and "." in a regular expression means "any character".
Consequently, all characters in the input are replaced.  You must use
"\." to match a literal dot.

> $ echo "some_script" | awk 'gsub("/","a") {print $0}'
> $
> 
> But must be:
> 
> $ echo "some_script" | awk 'gsub("/","a") {print $0}'
> $ some_script

Also not the case.  You have placed the call to gsub into the pattern
part of the pattern-action statement.  Consequently, it evaluates to 0
because there are no slashes in the input, and therefore the action is
never executed.  A correct action statement would be

        {gsub("/", a); print $0}

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