October 2001
Intermediate to advanced
1040 pages
22h 50m
English
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12.4. Positional Parameters and Command Line Arguments
12.4.1. Positional Parameters
Information can be passed into a script via the command line. Each word (separated by whitespace) following the scriptname is called an argument.
Command line arguments can be referenced in scripts with positional parameters; for example, $1 for the first argument, $2 for the second argument, $3 for the third argument, and so on. After $9, curly braces are used to keep the number as one number. For example, positional parameter 10 is referenced as ${10}. The $# variable is used to test for the number of parameters, and $* is used to display all of them. Positional parameters can be set or reset with the set command. When the set command is used, any positional ...
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