The grep command in Unix and Linux can be used to search for text between two words in a file. The grep command can be used with the -o option to extract only the matching text and with the -P option to enable Perl-compatible regular expressions (PCRE) mode, which allows for more advanced pattern matching.
Here’s an example of how to use grep to extract text between two words “start” and “end” in a file named file.txt:
grep -oP '(?<=start).*(?=end)' file.txt
The -o option extracts only the matching text, while the -P option enables PCRE mode. The regular expression (?<=start).*(?=end) matches any text that is immediately preceded by the word “start” and immediately followed by the word “end”.
This grep command will extract the text between the two words “start” and “end”, inclusive, and print it to the console.
You can also use a similar approach to extract text between two patterns in multiple files by using the grep command with the -r option, which searches for files recursively in a directory. For example:
grep -roP '(?<=start).*(?=end)' /path/to/directory
This command will search for all files in the directory /path/to/directory and its subdirectories, and extract text between the two words “start” and “end”.