Searches one or more
files for lines that match a regular expression
pattern. Regular expressions are described in Chapter 6. Exit status is 0 if any lines match, 1 if none match, and 2 for errors. See also
Don't suppress output lines with binary data; treat as text.
num lines of text that occur after the matching line.
Print the byte offset within the input file before each line of output.
num lines of text that occur before the matching line.
Treat binary files as specified. By default, grep treats binary files as such (
type is binary). If a matching string is found within a binary file, grep reports only that the file matches; nothing is printed for nonmatching binary files. If
type is without-match, grep assumes binary files don't match and skips them altogether. Same as -I. Using a
type of text causes grep to treat binary files as text and print all matched lines. Same as -a.
Print only a count of matched lines. With the -v or --invert-match option, count nonmatching lines.
num lines of leading and trailing context. Default context is 2 lines.
Marks matched text in red, or the contents of
GREP_COLOR environment variable. Optional
when can be auto, always, or never.