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Comment: fix a typo in the second legacy-shell example
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[[Anchor(faq25)]]
== How can I access positional parameters after $9? ==
Use {{{${10} }}}instead of {{{$10}}}. This works for ["BASH"] and KornShell, but not for older BourneShell implementations. Another way to access arbitrary positional parameters after $9 is to use {{{for}}}, e.g. to get the last parameter:

{{{
    for last
    do
        : # nothing
    done

    echo "last argument is: $last"
}}}

To get an argument by number, we can use a counter:

{{{
    n=12 # This is the number of the argument we are interested in
    i=1
    for arg
    do
        if [ $i -eq $n ]
        then
            argn=$arg
            break
        fi
        i=`expr $i + 1`
    done
    echo "argument number $n is: $argn"
}}}

This has the advantage of not "consuming" the arguments. If this is no problem, the {{{shift}}} command discards the first positional arguments:

{{{
    shift 11
    echo "the 12th argument is: $1"
}}}

Although direct access to any positional argument is possible this way, it's hardly needed. The common way is to use {{{getopts(3)}}} to process command line options (e.g. "-l", or "-o filename"), and then use either {{{for}}} or {{{while}}} to process all arguments in turn. An explanation of how to process command line arguments is available here: http://www.shelldorado.com/goodcoding/cmdargs.html
My name is Tomoko and I am studying Gender and Women's Studies and Occupational Therapy at Augusta / Italy.<<BR>>
<<BR>>
Also visit my web-site - [[http://host-a.net/u/danielross/Many_Approaches_to_Discover_Help_for_Alcoholism.pdf|How To Quit Drinking]]

My name is Tomoko and I am studying Gender and Women's Studies and Occupational Therapy at Augusta / Italy.

Also visit my web-site - How To Quit Drinking

BashFAQ/025 (last edited 2024-03-28 14:56:51 by emanuele6)