[pkgsrc/trunk]: pkgsrc/mk Improved the documentation.

[rillig <rillig%pkgsrc.org@localhost>]

details:   https://anonhg.NetBSD.org/pkgsrc/rev/3ffd16a70c35
branches:  trunk
changeset: 533748:3ffd16a70c35
user:      rillig <rillig%pkgsrc.org@localhost>
date:      Sat Sep 29 10:56:34 2007 +0000

description:
Improved the documentation.

diffstat:

 mk/find-prefix.mk |  30 ++++++++++++++++++++++++++++--
 1 files changed, 28 insertions(+), 2 deletions(-)

diffs (46 lines):

diff -r 88ebef8a0873 -r 3ffd16a70c35 mk/find-prefix.mk
--- a/mk/find-prefix.mk Sat Sep 29 10:23:08 2007 +0000
+++ b/mk/find-prefix.mk Sat Sep 29 10:56:34 2007 +0000
@@ -1,7 +1,28 @@
-# $NetBSD: find-prefix.mk,v 1.4 2005/11/28 05:54:17 jlam Exp $
+# $NetBSD: find-prefix.mk,v 1.5 2007/09/29 10:56:34 rillig Exp $
 #
 # This is a "subroutine" that can be included to find the installation
-# prefix of a package.
+# prefix of an installed package.
+#
+# Parameters:
+#
+# FIND_PREFIX
+#      A list of <VARNAME>=<pattern> pairs, where
+#
+#      * <pattern> is a package wildcard pattern (see pkg_info(8)),
+#      * <VARNAME> is the variable that will be set to the
+#        installation prefix for the package.
+#
+# Returns:
+#
+# <VARNAME>
+#      The prefix of the corresponding package, or ${LOCALBASE}
+#      if the package is not installed.
+#
+# Example:
+#
+# FIND_PREFIX:=        M4DIR=gm4
+# .include "../../mk/find-prefix.mk"
+# # ${M4DIR} now contains the installation prefix for the "gm4" package.
 #
 # The input variable is FIND_PREFIX, which is a list of VARNAME=<pattern>
 # pairs, where "VARNAME" is the variable that will be set to the
@@ -17,6 +38,11 @@
 
 .for _def_ in ${FIND_PREFIX}
 .  if !defined(${_def_:C/=.*$//})
+
+# XXX: Is this *_DEFAULT variable really necessary? The default value
+# can be easily embedded in the shell code. What if VARNAME is set to
+# PKG_APACHE, for example?
+#
 ${_def_:C/=.*$//}_DEFAULT?=    ${LOCALBASE}
 _${_def_:C/=.*$//}_cmd=                \
        ${PKG_INFO} -qp ${_def_:C/^[^=]*=//:Q} 2>/dev/null |            \