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Display a random man page

Terminal - Display a random man page
man $(ls /bin | shuf | head -1)
2010-08-20 23:12:51
Functions: head ls man
1
Display a random man page

I'm not sure why you would want to do this, but this seems a lot simpler (easier to understand) than the version someone submitted using awk.

Alternatives

There are 3 alternatives - vote for the best!

Terminal - Alternatives
dir="/bin"; man $(ls $dir |sed -n "$(echo $(( $RANDOM % $(ls $dir |wc -l | awk "{ print $1; }" ) + 1 )) )p")
2010-08-20 16:31:50
User: camocrazed
Functions: dir ls man sed
Tags: man sed awk echo wc
-2

Broaden your knowledge of the utilities available to you in no particular order whatsoever! Then use that knowledge to create more nifty one-liners that you can post here. =p

Takes a random number modulo the number of files in $dir, prints the filename corresponding to that number, and passes it as an argument to man.

man $(ls /bin | sed -n $((RANDOM % $(ls /bin | wc -l) + 1))p)
2010-08-20 17:15:33
User: putnamhill
Functions: ls man sed wc
Tags: man sed ls wc random
-2

Great idea camocrazed. Another twist would be to display a different man page based on the day of the year. The following will continuously cycle through all man pages:

man $(ls /bin | sed -n $(($(date +%j) % $(ls /bin | wc -l)))p)
man $(ls -1 /usr/share/man/man?/ | shuf -n1 | cut -d. -f1)
2010-08-20 23:36:10
User: dooblem
Functions: cut ls man
Tags: man sort shuf
-2

Another one.

Maybe not the quicker because of the sort command, but it will also look in other man sections.

updated with goodevilgenius 'shuf' idea

(cd /bin; set -- *; x=$((1+($RANDOM % $#))); man ${!x})
man $(/bin/ls /bin | awk '{ cmd[i++] = $0 } END { srand(); print cmd[int(rand()*length(cmd))]; }')
2010-08-20 17:31:02
User: emilsit
Functions: awk man
Tags: man awk
-4

Build an awk array with all commands and then select a random one at the end.

This avoids spawning extra processes for counting with wc or generating random numbers.

Explicitly call /bin/ls to avoid interactions with aliases.

Know a better way?

If you can do better, submit your command here.

What others think

Although this command is short and neat, it would not scale well to a directory containing many file names. Shuffling, say, 20000 file names, would be much more onerous than merely choosing a random number between 1 and 20000.

Comment by quintic 328 weeks and 5 days ago

Your point of view

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