Menu
The basic grep syntax when searching multiple patterns in a file includes using the grep command followed by strings and the name of the file or its path. The patterns need to be enclosed using single quotes and separated by the pipe symbol. Use the backslash before pipe | for regular expressions.
Grep Multiple Patterns To search for multiple patterns, use the OR (alternation) operator. The alternation operator | (pipe) allows you to specify different possible matches that can be literal strings or expression sets. This operator has the lowest precedence of all regular expression operators.
The GREP command - an overviewBy default, grep displays the matched lines, and it can be used to search for lines of text that match one or more regular expressions, and it outputs only the matched lines.
You can use
grep 'string1' filename | grep 'string2'
Or
grep 'string1.*string2\|string2.*string1' filename
I think this is what you were looking for:
grep -E "string1|string2" filename
I think that answers like this:
grep 'string1.*string2\|string2.*string1' filename
only match the case where both are present, not one or the other or both.
To search for files containing all the words in any order anywhere:
grep -ril \'action\' | xargs grep -il \'model\' | xargs grep -il \'view_type\'
The first grep kicks off a recursive search (r), ignoring case (i) and listing (printing out) the name of the files that are matching (l) for one term ('action' with the single quotes) occurring anywhere in the file.
The subsequent greps search for the other terms, retaining case insensitivity and listing out the matching files.
The final list of files that you will get will the ones that contain these terms, in any order anywhere in the file.
If you have a grep with a -P option for a limited perl regex, you can use
grep -P '(?=.*string1)(?=.*string2)'
which has the advantage of working with overlapping strings. It's somewhat more straightforward using perl as grep, because you can specify the and logic more directly:
perl -ne 'print if /string1/ && /string2/'
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With