X Power Tools

Chapter 7. Running X Clients

Running X Clients

Running an X client is generally a fairly simple proposition, but it is different from running a character application. This chapter covers:

• Running clients in the background (Section 7.2)

• Requesting a certain window size and position (Section 7.3)

• Running nongraphical programs on an X display (Section 7.4)

Displayspecs (Section 1.12) are a closely related topic.

Background Operation

Most X applications don’t need to interact with the user through the standard input and output; therefore, when starting them from a shell prompt, you may as well put them into the background. Simply add an ampersand to the end of the command name:

	$ kcalc &

If you close the terminal from which you started the client, the client will (in almost all cases) be terminated. To avoid this, use the nohup command:

	$ nohup kcalc &

Tip

Some error messages may be sent to standard error, which may not be visible when the client is run in the background. When debugging the operation of a client, it may be necessary to redirect stdout and stderr to a file:

	$ nohup kcalc >kcalc.log 2>&1 &

Geometry

In X Window parlance, geometryrefers to the size and position of windows. Clients may request a particular geometry when placing a new window, but the window manager can override the request and force another geometry.

The units used for window size vary by application. Terminal windows, for example, are usually sized in text rows and columns (for example, 80 x 24 or 132 x 44); many applications, ...