http://www.bashguru.com/2009/11/how-to- pass-arguments-to-shell-script.html Sunday, November 15, 2009 How to Pass Arguments to Shell Script Like UNIX commands, shell scripts also accept arguments from the command line. They can, therefore, run non interactively and be used with redirection and pipelines. Positional Parameters: Arguments are passed from the command line into a shell program using the positional parameters $1 through to $9. Each parameter corresponds to the position of the argument on the command line. The first argument is read by the shell into the parameter $1, The second argument into $2, and so on. After $9, the arguments must be enclosed in brackets, for example, ${10}, ${11}, ${12}.Some shells doesn't support this method. In that case, to refer to parameters with numbers greater than 9, use the shift command; this shifts the parameter list to the left. $1 is lost,while $2 becomes $1, $3 becomes $2, and so on. The inaccessible tenth parameter becomes $9 and can then be referred to. Example: #!/bin/bash # Call this script with at least 3 parameters, for example # sh scriptname 1 2 3 echo "first parameter is $1"
This doc contains detail example of how to handle argument in shell script
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http://www.bashguru.com/2009/11/how-to-pass-arguments-to-shell-script.htmlSunday,
Noember 1!, 2009"ow to #ass $rguments to Shell Script Like UNIX
commands, shell scripts also accept arguments from the command
line.They can, therefore, run non interactively and be used with
redirection andpipelines.Positional Parameters:rguments are passed
from the command line into a shell program using thepositional
parameters !" through to !#. $ach parameter corresponds to
theposition of the argument on the command line.The first argument
is read by the shell into the parameter !", The secondargument into
!%, and so on. fter !#, the arguments must be enclosed inbrackets,
for e&le, !'"(), !'""), !'"%).*ome shells doesn+t support
thismethod. In that case, to refer to parameters with numbers
greater than #, usethe shift command, this shifts the parameter
list to the left. !" is lost,while!% becomes !", !- becomes !%, and
so on. The inaccessible tenth parameterbecomes !# and can then be
referred to.Example:./0bin0bash. 1all this script with at least -
parameters, for e&le. sh scriptname " % -echo 2first
parameter is !"2echo 2*econd parameter is !%2echo 2Third parameter
is !-2e&it (Output:3root4localhost 56. sh parameters.sh 78 #
-7first parameter is 78*econd parameter is #Third parameter is
-73root4localhost 56. sh parameters.sh 7 9 -first parameter is
7*econd parameter is 9Third parameter is - In addition to these
positional parameters, there are a few other specialparameters used
by shell.Their significance is noted bellow.!: ; It stores the
complete set of positional parameters as a single string.!4 ; *ame
as !:, efers to the name of the script itself.Setting Values of
Positional Parameters?ou can+t technically call positional
parameters as shell variables because allvariable names start with
a letter. @or instance you can+t assign values to !",!%.. etc.
!"A"(( or !%Avenu is simply not done. There is one more way to
assignvalues to the positional parameters, using the set command.$
set Helping hands are holier than praying lipsThe above command
sets the value !" with BCelpingD , !% with BhandsD and so on.To
verify, use echo statement to display their values.$ echo $1 $2 $3
$ $! $" $#Celping hands are holier than praying lips?ou can simply
use !: or !4$ echo $$Celping hands are holier than praying lips$
echo $%Celping hands are holier than praying lips&sing Shift on
Positional ParametersEe have used set command to set upto #
words.
