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3 Fundamentals of the Linux system and terminal usage

Figure 3.26 The bash script for fetching random man pages

find /usr/share/man/man1 -type f | shuf | awk -F
‘/’ ‘{print $6}’ | sed ‘s/.gz//g’ | head -1
First, we utilize the find command to search through a directory
containing mostly user-focused tools at the path “/usr/share/man/
man1” and include only files.
Then, we use shuf to mix them in a random order. Next, we clear
the output through awk, which divides every line into individual fields
(using ‘/’ as the separator) and returns the sixth field of every line.
Then, we globally remove the unnecessary file extensions “.gz” by sub-
stituting them with an empty space using sed (Figure 3.25). Finally,
we select only the first line using the head.
We are using the variable random_manpage to store the values
generated by the aforementioned command, using the command sub-
stitution expression $():

random_manpage=$(find /usr/share/man/man1 -type
f | shuf | awk -F ‘/’ ‘{print $6}’ | sed ‘s/.
gz//g’ | head -1)
To complete our bash script, we will pass the variable to the man,
which will open the man page of the specified command (Figure 3.26):

man $random_manpage
Finally, save and exit the file, and make it executable for the current
user via the chmod command:
chmod u+x randman
Now, the program can be executed from the home folder by running
./randman (“./” stands for the current directory).

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