Manipulation of text files
diff compares two files and reports the differences. grep search file for pattern (regular expression). sort sorts textfiles.
head prints first 10 lines of file.
tail prints (surprise) last 10 lines of file.
a2ps
Redirection of input or output
To redirect the input or output for a program invoked by a command you use < and >. For example to redirect the output from a directory listing (command ls) to outputfile , you would do the following: ls > outputfile . To redirect the input from a file, you use <
Pipelines
Pipelines allow you to let the output of one program be used as input to another program. This is done in a command line containing several commands separated by bar characters “ ”. Each bar denotes a pipeline which “pipes” the output of the command to the left of the bar to the input of the command to the right of the bar.
Example: let's assume that you have created a program that outputs textlines, and you want to see the
first 15 lines containing the word “hello world”, you would execute the following: myprogram
grep helloworld head
11 Desktop enviroments in the data bars
The graphics subsystem in Linux is an implementation of The X Window System or just X for short. It implements the basic graphic and windowing primitives and it is totally network transparent (unlike the graphics system of another
A window manager works on top of the graphics subsystem and it implements the
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