If I have comments embedded in line-continuations in a script with a pipeline, will they get processed for every record flowing through the pipeline?

For instance, I have a script:

#!/bin/sh
sed 'my_sed_program' input_file \
| awk '
#This is comment line 1.
#This is comment line 2.
#This is comment line N......
{ do_whatever }
'
exit 0


If my "input_file" is pretty large, will those multiple comments in my awk program be processed (and of course skipped) for every input line? Or are they "stripped" on the first pass through and not processed again for the duration of my process?

In other words, from a performance perspective, would it be better to have my imbedded comments outside of the pipeline?

Please use ***[code][/code]*** tags around your code and data, to preserve the original formatting and to improve readability. Do not use quote tags, bolding, colors, "start/end" lines, or other creative techniques. Thanks.


The comments you have written here are actually awk comments, not shell comments. But in any case I'm almost certain that they are excluded during the initial parsing stage. It would be crazy to do it any other way, since the parser doesn't need them.

You might look it up in the gawk reference manual:

http://www.gnu.org/software/gawk/man...ode/index.html

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Hi.

I looked at the source code of GNU awk. David is right, comments are ignored by lexical analyzer which runs only once.

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