grep

Linux · Text · available in the simulator

What it does

Search for a pattern in one or more files.

Syntax

grep [opciones] patrón [archivo...]

Options and parameters

• -i

  Perform case-insensitive matching.

  grep -i error log.txt
• -r

  Search recursively within directories.

  grep -rin "error" .
• -n

  Prefix output with the line number of each match.

• -v

  Invert match to select non-matching lines.

  grep -v "^#" config.conf
• -E

  Use extended regular expressions; equivalent to egrep.

  grep -E "error|warn" log.txt
• -c

  Print only the count of matching lines.

• -R

  Like -r, but follow all symbolic links.

• -l

  Print only the names of files with matches.

• -w

  Match only whole words, not partial matches.

• -o

  Print only the matched parts of a line.

• -F

  Treat pattern as a literal string; equivalent to fgrep.

• -A

  Print the specified number of trailing context lines.

  grep -A3 error log.txt
• -B

  Print the specified number of leading context lines.

• -C

  Print the specified number of leading and trailing context lines.

• --include

  Limit recursive search to files that match the pattern.

• --exclude

  Skip files that match the pattern from search.

Usage examples

• grep error archivo.txt
• grep -i error log.txt
• grep -rn TODO src/
• grep error app.log
• grep -rin 'error' .
• grep -rin "error" .
• grep -v "^#" config.conf
• grep -E "error|warn" log.txt
• grep -A3 error log.txt

Related commands

• awk
• cat
• cut
• diff
• head
• less