Re: Command Substitution in AC_ARG_WITH Help Strings

[Andreas Schwab]

Keith Marshall <address@hidden> writes:

> Hello,
>
> I would like to implement a configure option which would have the effect of
>
> AC_DEFUN([MY_LANGUAGE_SET],
> [AC_ARG_WITH([languages],
> AS_HELP_STRING([--with-languages=LIST],
> [install language files in LIST, a comma separated subset of '$1']),
> [languages=$withval],
> [languages=en])])
>
> MY_LANGUAGE_SET([`cd lang; echo ?? | tr " " ,`])
>
> and have the result of the command substitution
>
>    `cd lang; echo ?? | tr " " ,`
>
> appear in the `configure --help' output.

This won't do the right thing if configure is executed outside the source
directory (for buiding in a separate directory).

> Given these limitations, can anyone suggest a better mechanism for achieving 
> this objective?

Use esyscmd to interpolate the output of the command at configure creation
time.

Andreas.

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Andreas Schwab, SuSE Labs, address@hidden
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