SHELL

grep return n characters before or after match

# Basic syntax:
grep -o -E '.{0,3}string.{0,4}' your_file.txt
# Where:
#	- This expression returns 3 characters before string and 4 after
#	-o specifies returning only the matching text, not the entire line
#	-E specifies allowing extended regular expressions (some answers
#		change this to -P, but that doesn't work on macOS)
# Note, add the -m flag if you want to specify the number of matches to
#	allow per line (e.g. -m 2)