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Functions

Display a random man page

Terminal - Display a random man page
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
-4
Display a random man page

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.

Alternatives

There is 1 alternative - vote for the best!

Terminal - Alternatives
man $(ls /bin | shuf | head -1)
2010-08-20 23:12:51
Functions: head ls man
Tags: man
1

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.

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) % $(ls /bin | wc -l)))p)
(cd /bin; set -- *; x=$((1+($RANDOM % $#))); man ${!x})
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
-3

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

Know a better way?

If you can do better, submit your command here.

What others think

I like this better than my version. Evidently I need to learn how to write awk scripts

Comment by camocrazed 190 weeks and 4 days ago

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