Difference between revisions of "How to use positional parameters"

From Linux Shell Scripting Tutorial - A Beginner's handbook
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The number of arguments passed to the script : 3
 
The number of arguments passed to the script : 3
 
The value of all command-line arguments : bmw ford toyota</pre>
 
The value of all command-line arguments : bmw ford toyota</pre>
 +
Try the following examples:
 +
<source lang="bash">ls /tmp
 +
./math 10 + 2
 +
~/scripts/addzone cyberciti.com
 +
~/scripts/adddomain cyberciti.biz '74.86.48.99' '2607:f0d0:1002:11::4'
 +
/etc/init.d/named reload
 +
/usr/rc.d/jail restart cyberciti.biz</source>
 +
{| style="cellpadding="20" cellspacing="0" border="1"  width="100%"
 +
! style="background:#ffdead;"| Shell script name ($0)
 +
! style="background:#ffdead;"| Total number of arguments
 +
! style="background:#ffdead;"| Actual Command line argument ($1,..,$9)
 +
|-
 +
|}

Revision as of 15:22, 5 September 2009

All command line parameters ( positional parameters ) are available via special shell variable $1, $2, $3,...,$9.

How Do I Access Command-Line Arguments

Create a simple shell script called cmdargs.sh:

#!/bin/bash
echo "The script name : $0"
echo "The value of the first argument to the script : $1"
echo "The value of the second argument to the script : $2"
echo "The value of the third argument to the script : $3"
echo "The number of arguments passed to the script : $#"
echo "The value of all command-line arguments : $*"

Save and close the file. Rut it as follows:

chmod +x cmdargs.sh
./cmdargs.sh bmw ford toyota

Sample outputs:

The script name : ./cmdargs.sh
The value of the first argument to the script : bmw
The value of the second argument to the script : ford
The value of the third argument to the script : toyota
The number of arguments passed to the script : 3
The value of all command-line arguments : bmw ford toyota

Try the following examples:

ls /tmp
./math 10 + 2 
~/scripts/addzone cyberciti.com
~/scripts/adddomain cyberciti.biz '74.86.48.99' '2607:f0d0:1002:11::4' 
/etc/init.d/named reload
/usr/rc.d/jail restart cyberciti.biz
Shell script name ($0) Total number of arguments Actual Command line argument ($1,..,$9)