-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 According to Dr. David Kirkby on 8/12/2009 3:18 AM: > What's the best way to check if an environment variable is set? See AC_ARG_VAR, http://www.gnu.org/software/autoconf/manual/autoconf.html#Setting-Output-Variables, for how to treat SAGE_USE_BROKEN_TOOLS as a precious variable. > I want > to allow a user to set an environment variable > > $ SAGE_USE_BROKEN_TOOLS=yes > $ export SAGE_USE_BROKEN_TOOLS > > then the configure script check if SAGE_USE_BROKEN_TOOLS is set to 'yes' > or not and behave differently whether or not it is set. Ultimately, you should teach your users to prefer: ./configure SAGE_USE_BROKEN_TOOLS=yes rather than your approach of: export SAGE_USE_BROKEN_TOOLS=yes ./configure as the former will remember the user's choice at the time of the configure even if they subsequently change their environment. - -- Don't work too hard, make some time for fun as well! Eric Blake ebb9@xxxxxxx -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (Cygwin) Comment: Public key at home.comcast.net/~ericblake/eblake.gpg Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAkqCwwQACgkQ84KuGfSFAYBxRgCgxcPUPNnxBAXWR5d90QnUCTlY TSMAnizTtpziz/b3qVAWkBptDF8efRHG =/hB0 -----END PGP SIGNATURE----- _______________________________________________ Autoconf mailing list Autoconf@xxxxxxx http://lists.gnu.org/mailman/listinfo/autoconf
