MS-DOS v6.22 Help: Shift

------------------------- MS-DOS v6.22 Help: Shift -------------------------
<Notes> <Examples>                                               <Index>
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                                   SHIFT

Changes the position of replaceable parameters in a batch program.

Syntax

    SHIFT

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<Syntax> <Examples>
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                                SHIFT--Notes

How the SHIFT command works

The SHIFT command changes the values of the replaceable parameters %0
through %9 by copying each parameter into the previous one. In other words,
the value of %1 is copied to %0, the value of %2 is copied to %1, and so on.
This is useful for writing a batch file that performs the same operation on
any number of parameters.

Working with more than 10 command-line parameters

You can also use the SHIFT command to create a batch file that can accept
more than 10 parameters. If you specify more than 10 parameters on the
command line, those that appear after the tenth (%9) will be shifted one at
a time into %9.

Shifting parameters back

There is no backward SHIFT command. Once you carry out the SHIFT command,
you cannot recover the first parameter (%0) that existed before the shift.

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                               SHIFT--Example

The following batch file, MYCOPY.BAT, shows how to use the SHIFT command
with any number of parameters. It copies a list of files to a specific
directory. The parameters are the directory name followed by any number of
filenames.

    @echo off
    rem MYCOPY.BAT copies any number of files
    rem to a directory.
    rem The command uses the following syntax:
    rem mycopy dir file1 file2 ...
    set todir=%1
    :getfile
    shift
    if "%1"=="" goto end
    copy %1 %todir%
    goto getfile
    :end
    set todir=
    echo All done

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