sed /pat/!d without using sed (no RE; limited to shell patterns aka globbing)

se(){ while read a;do [ "$a" != "${a#*[email protected]*}" ]&&echo $a;done ;} # usage: se pattern # use in place of sed /pat/!d where RE are overkill
POSIX requires this "string truncating" functionality. might as well use it, at least for very small tasks where invoking sed and using RE is overkill.

By: argv
2011-04-06 03:37:40

What Others Think

You need to quote "$a" in the echo or it'll drop multiple spaces from the input. e.g. echo "a b"|se a a b
splante · 517 weeks and 1 day ago
splante: thank you. i have also used this one-liner as a simple way to transform tabs to spaces, e.g., where output from a program wraps on the terminal solely because it uses tabs, making it more difficult to read. fstat | se pattern if we quote the "$a" variable then of course we'll get the tabs. but in other situations quoting "$a" is useful. e.g. to prevent the shell from expanding certain characters. imagine if some program is listening on an internet socket, and you do netstat | se LIS you might not like what you get for the output, unless you have put quotes around "$a". it seems this website might also benefit from some added attention to shell quoting: i can only see one space between a and b in your example.
argv · 517 weeks and 1 day ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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