gsub

[kwal]

Hello!
I need some help with gsub. I wonder why gsub doesn't need a print statement. If you place gsub between braces, you need a print statement, but without those braces, the thing you want will be printed without a specific statement.
Who can help me?

 

[aigles]

If you use gsub as a pattern, lines with substitution are selected? If there is no action specified, the default action is "print".

awk 'gsub(&quot;[Aa]&quot;,&quot;!&quot' <<EOD
First test line
Another test line
Last line
EOD

will give :
!nother test line
L!st line


If you use gsub in an action (inside braces), the substitution occurs but if you want to see the result you must use a print statement.

awk '{ gsub(&quot;[Aa]&quot;,&quot;!&quot ; print}' <<EOD
First test line
Another test line
Last line
EOD

will give :
First test line
!nother test line
L!st line
Jean Pierre.