CODEWITHSUNDEEP
command-linegrep
J Freebird
J Freebird

Reputation: 3910

egrep regex match line break

I need to match string update sims in .sql files to prevent any update to table sims. I have cat test.sql | grep -iE '^\s*UPDATE\s+sims,*\s+', which will not wrongly match, say update simsfdafsa. It will match update sims set and update sims, table1, table2....

But I cannot match any line break char. If someone wrote:

update sims
set dfa=fdag

The grep fails. There's a line break after the sims above. I tried \n and \s, but neither worked. I wonder how to match line break in egrep?

Upvotes: 0

Views: 423

Answers (1)

Cwissy
Cwissy

Reputation: 2156

using this as a test file:

cat ~/tmp/test
update sims
set dfa=fdag
update simsafing
update sims, test1
update simss

this regex parses it as you require:

egrep 'update sims$|sims[, ]' ~/tmp/test

update sims
update sims, test1

edit

this page https://www.gnu.org/software/sed/manual/html_node/Regular-Expressions.html explains all the regex patterns that sed knows about (it is basic regex). Because sed is 'greedy' (once you've read that page you'll know what that means) it attempts to match as much of the pattern as possible, so [, ] will match as many spaces or commas in a run as possible.

Upvotes: 1

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