Introduction to xclock:

• In Linux, the xclock package contains a simple clock application which is used in the default xinit configuration.
• This package is not a part of the Xorg katamari and is provided only as a dependency to other packages or for testing the completed Xorg installation.
• This package is known to build and work properly using an LFS-8.0 platform.

Installation of xclock:

• Install xclock by running the following commands:

./configure $XORG_CONFIG &&
make

• This package does not come with a test suite.

Now, as the root user:

 make install

How to install xclock on Red Hat Linux:

• To identify if xclock is installed and if it is not installed, how to install it on Red Hat Linux system.
• If xclock is not installed, invoking xclock will return command not found message as seen below

$ xclock
-bash: xclock: command not found

• xclock whereis, which and rpm –qa commands confirm that is not installed

$ whereis xclock
xclock:

$ which xclock
/usr/bin/which: no xclock in (/usr/lib64/qt-3.3/bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/b

• Use rpm –qa to find if the package xorg-x11-apps is installed.

# rpm -qa  | grep -i xorg-x11-apps
#

The above command returns nothing. Which means that there is no rpm for xclock installed on the system. –qa stands for query all.