I need to search a text file for a word count. The file contains lines of sentences and I only care about the number of times a word shows up not the number of lines. How do I tell grep to search for words instead of lines?
For instance if I use, grep -c '^ab' (words that start with ab), it only returns the number of lines that begin with ab, not the number of words that begin with ab.
With GNU grep you can use the -o flag to get all the matches, and then count them afterwards wc -l:
grep -o '\<ab' file.txt | wc -l
Or I suppose you could count with grep itself:
grep -o '\<ab' file.txt | grep -c ''
("\<" means "start of a word".)
\<a[A-Za-z]*b\>; if what you count as "words" can have other things in them like hyphens or underscores or digits, you may need to add to what's in the brackets.
-o doesn't use a different kind of regex; it is just an option for grep which makes it so it only outputs the matches rather than the entire lines containing the matches (grep's normal behavior), and if there is more than one match on the same line, it puts them on separate lines in the output. See the man page for GNU grep (or man grep in the terminal).
If you want to count words in file.txt, not lines, simply put each word on its own line:
tr " " "\n" file.txt | grep -c '^ab'
tr " " "\n" < file.txt | grep -c '^ab'.
grepthat has the non-standard-ooption? Are you interested in substrings of words, likeworldin the stringotherworldly? If not, what constitute a word? IsUnix-likeone word, or the two wordsUnixandlikeand doesyou'dmatch the wordyou?grepping without the^, the beginning-of-line anchor.ab”. Please clarify: are you looking for a word, or for all words that match a pattern? (2) If you want to look for a pattern, think about multiple occurrences. For example, if you were looking for all words containingab, would “habitable” count as one or two?