2. Using SandUhr

2.1. Starting SandUhr

There are two ways to start the SandUhr program. The easy method is to use GNOME's start menu: SandUhr is installed in the System menus as Programs->Utilities->SandUhr. The program first opens a dialog to enter the alarm time. After closing this dialog the actual alarm clock launches.

Alternatively you can launch SandUhr from the command line. The calling syntax is as follows:

sanduhr [options] [time]
	

The time argument defines the time when the alarm action is to be triggered. It is a string whose format is explained in Section 2.2. If no alarm time is given, the program opens a dialog window to enter this time there. Options may be chosen among these:

-h, --help

shows the complete list of options.

-m MSG, --message=MSG

Use MSG as the alarm message.

2.2. The Alarm Time

SandUhr's main use is to wait until a specified alarm time is reached. You tell this time to the program with the help of a time string, either as a command line argument or entered into the dialog window. There are two fundamentally different ways to specify the alarm time. You may specify the length of the alarm period or you may specify the point of time when the alarm should occur.

Relative time specifications give the length of the time interval. They always start with a + sign, which is followed by the interval's length. Examples are +30s (wait for 30 seconds) and +1h30m (one hour and a half). The following abbreviations are used.

Absolute time specifications directly give the alarm time. They always start with a digit. Examples are 20:15 (a quarter past eight in the evening) and 2003-12-31 23:59:59 (the very end of the year 2003).

Tip

As the preceding example illustrates, absolute time specifications may include spaces. When entering these on the command line, you have to enclose the whole expression within double quotes, to prevent the shell from splitting it.

The syntax for absolute time specifications is:

[year-month-day] hour:minute[:second]
	
where year is a four-digit number, the month is in the range 1 through 12, the day of the month is in the range 1 through 31, hour is the number of hours past midnight, in the range 0 through 23, and the minute and the second are in the range `0' through `59'.