Grep output pattern

Question

If I have a bash file with following content:

ls \
/tmp

Is there a way to grep this file and get

ls \
/tmp

instead of

ls \

?

Please notice that other behaviors of grep should remain same if input is a large file and has other match patterns.

Thanks!

Your question is a little vague to me,can you post the current grep command your using? — Tobrun
– Tobrun, Commented Oct 5, 2012 at 17:39

William Pursell · Accepted Answer · 2012-10-05 17:50:17Z

1

Assuming you want to treat the final \ as a line continuation character, you can use awk to concatenate the lines:

awk '{ while( sub( "\\\\$", "" )) { getline n; $0 = $0 n; }} /ls/' input-file

This removes the line continuation character and combines everything into one line, then prints the line if if matches the regex ls.

answered Oct 5, 2012 at 17:50

William Pursell

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2 Comments

This is great! Is it hard if I want add \ back?

Probably easiest to not delete it in the first place. Use awk '{ while( /\\$/ ) ... instead.

nneonneo · Accepted Answer · 2012-10-05 18:36:10Z

1

You can use the context options, -A (lines after), -B (lines before), and -C (lines context, both before and after):

$ grep -A1 ls test.sh
ls \
/tmp

answered Oct 5, 2012 at 17:40

nneonneo

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+1 for the answer. Shouldn't you use -A1 instead of -C1 so it matches what the OP wanted.

Thanks for the answer. What if the bash file contains: ls \ /var \ /tmp