How to search Linux man pages (e.g. with grep)

Question

I'm looking for information on the -X option of curl. However, the documentation is quite lengthy and I have to scroll down for quite a long time to get to this option. Instead, I'd like to do something like

man curl | grep -X

to get the line containing "-X". (I would also do this in conjunction with the option -A 10 to get the 10 lines after the match). However, if I try this I get

grep: option requires an argument -- 'X'
Usage: grep [OPTION]... PATTERN [FILE]...
Try 'grep --help' for more information.

Any ideas on how to use grep together with man, or more generally on how to search man pages for specific lines?

Answer 1

You have to tell grep that -X is not an option, but the pattern to look for:

man curl | grep -- '-X'

-- indicates the end of options. Without it, grep thinks that -X is an option.

Alternatively, you can use -e to indicate that what follows is a pattern:

man curl | grep -e '-X'

If you want to see the complete man page but skip directly to the first occurrence of -X, you can use a command line option to less:

man curl | less +/-X

Typing N repeatedly then takes you to the following occurrences.