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When I grep the man page of the find command for matches to type it returns a lot of search results that I don't want. Instead I want to use a command that returns only the search results for -type.

The command man find | grep -type doesn't work. It returns:

grep: invalid option -- 't'
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    Do you want just the individual lines of the formatted man page that contain the string -type, or do you want, say, the entire paragraph or two that describes what -type does? Commented Nov 17, 2016 at 23:34
  • I want to know how to do it both ways, grepping for the individual lines that contain the string -type would be enough for the way I usually search the man pages, however returning the entire paragraph or two that describes what -type does would be very useful to do at least one time.
    – karel
    Commented Nov 17, 2016 at 23:51
  • BTW, if viewing a web page is an alternative, Idan Kamara at explainshell.com has done a great job of extracting the portions of man pages that describe command options. See, for example, explainshell.com/explain?cmd=find+-type+f to see just what the -type option does. Commented Nov 18, 2016 at 0:10

2 Answers 2

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If you want to grep for a pattern beginning with a hyphen, use -- before the pattern you specify.

man find | grep -- -type

If you want more info, for example the entire section describing an option, you could try using Sed:

$ man find | sed -n '/-mindepth/,/^$/p'
   -mindepth levels
          Do  not apply any tests or actions at levels less than levels (a
          non-negative integer).  -mindepth  1  means  process  all  files
          except the command line arguments.

However, this won't work for every option you might search for. For example:

$ man find | sed -n '/^[[:space:]]*-type/,/^$/p'
   -type c
          File is of type c:

Not very helpful. Worse, for some options you could be misled into thinking you'd read the whole text about the option when you really hadn't. For example, searching -delete omits the very important WARNING contained as a second paragraph under that heading.


My recommendation is to use a standard call to man with the LESS environment variable set. I use it quite commonly in my answers on this site.

LESS='+/^[[:space:]]*-type' man find

To learn more about how this works, see:

LESS='+/^[[:space:]]*LESS ' man less
LESS='+/\+cmd' man less
LESS='+/\/' man less

If you just want to find the option quickly and interactively in the man page, learn to use less's search capabilities. And also see:

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  • Thank you for posting. The commands in your answer returned the results that I was looking for. I will accept an answer after a day or two, so please be patient.
    – karel
    Commented Nov 18, 2016 at 0:02
  • @karel, no problem, I'm very patient. :) A little puzzled, though: I know you can't start a bounty on a question for two days, but I believe the time limit before you can accept an answer is only 15 minutes or so.
    – Wildcard
    Commented Nov 18, 2016 at 0:06
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    man find | sed -n '/-type/,/^$/p' gives lot more than what you posted as it will match -type anywhere in the line... am working on small script myself to search man or help (for builtin) and currently using awk which still has few quirks to solve.. awk -v RS= -v rx="^\\\s*$arg\\\>" '$0 ~ rx' "$file" where arg would be -type in this case
    – Sundeep
    Commented Nov 18, 2016 at 2:44
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    BTW, @Sundeep, you might want to try parsing the underlying troff files containing the original man page info with format information, instead of the text output of the man command.
    – Wildcard
    Commented Nov 18, 2016 at 2:52
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    @Sundeep, here's the starting point for you. (Be sure to follow the link in that answer.) There's a LOT to know about troff. Ping me in chat when you finish diving down the rabbit hole. :)
    – Wildcard
    Commented Nov 18, 2016 at 3:07
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Or pipe to less and feed that a search term:

man 1 find | less -p ' -type'

(This may fail depending on exactly what less is feed, e.g. if -type has been bolded up with backspaces.)

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  • Pipe it through col -bx first.
    – Wildcard
    Commented Nov 18, 2016 at 3:08

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