?RCS: $Id: Inhdr.U 167 2013-05-08 17:58:00Z rmanfredi $
?RCS:
?RCS: Copyright (c) 1991-1997, 2004-2006, Raphael Manfredi
?RCS: 
?RCS: You may redistribute only under the terms of the Artistic License,
?RCS: as specified in the README file that comes with the distribution.
?RCS: You may reuse parts of this distribution only within the terms of
?RCS: that same Artistic License; a copy of which may be found at the root
?RCS: of the source tree for dist 4.0.
?RCS:
?RCS: $Log: Inhdr.U,v $
?RCS: Revision 3.0.1.2  1995/05/12  12:01:31  ram
?RCS: patch54: deleted tabs that caused some /bin/sh to core dump (ADO)
?RCS:
?RCS: Revision 3.0.1.1  1994/10/29  15:55:01  ram
?RCS: patch36: call ./whoa explicitely instead of relying on PATH
?RCS:
?RCS: Revision 3.0  1993/08/18  12:05:01  ram
?RCS: Baseline for dist 3.0 netwide release.
?RCS:
?X:
?X: This unit checks wether a set of header files exists or not.
?X:	If the first header is not found, the function tries to locate
?X: the next header, and so on, until one is found or there is no
?X: more header in the list.
?X:
?X: To use it, say:
?X: set header i_header [ header2 i_header2 ... ]
?X: eval $inhdr
?X:
?MAKE:Inhdr: test Findhdr Whoa
?MAKE:	-pick add $@ %<
?LINT:define inhdr
?V:inhdr
?S:inhdr:
?S:	This shell variable is used internally by Configure to check
?S:	wether a set of headers exist or not. A typical use is:
?S:		set header i_header [ header2 i_header2 ... ]
?S:		eval $inhdr
?S:	That will print a message, saying wether header was found or
?S:	not and set i_header* accordingly. If the first header is not
?S: found, we try the next one, until the list is empty or one is found.
?S:.
?T:xxx xxf var td xxnf tu yyy instead was cont
: define an alternate in-header-list? function
inhdr='echo " "; td=$define; tu=$undef; yyy=$@;
cont=true; xxf="echo \"<\$1> found.\" >&4";
case $# in 2) xxnf="echo \"<\$1> NOT found.\" >&4";;
*) xxnf="echo \"<\$1> NOT found, ...\" >&4";;
esac;
case $# in 4) instead=instead;; *) instead="at last";; esac;
while $test "$cont"; do
	xxx=`./findhdr $1`
	var=$2; eval "was=\$$2";
	if $test "$xxx" && $test -r "$xxx";
	then eval $xxf;
?X: Next line shifted left 1 tabstop to avoid sh core dump on MachTen 2.1.1.
	eval "case \"\$$var\" in $undef) . ./whoa; esac"; eval "$var=\$td";
		cont="";
	else eval $xxnf;
?X: Likewise, the next line has been shifted left 1 tabstop -- ADO, 08/03/95
	eval "case \"\$$var\" in $define) . ./whoa; esac"; eval "$var=\$tu"; fi;
	set $yyy; shift; shift; yyy=$@;
	case $# in 0) cont="";;
	2) xxf="echo \"but I found <\$1> $instead.\" >&4";
		xxnf="echo \"and I did not find <\$1> either.\" >&4";;
	*) xxf="echo \"but I found <\$1\> instead.\" >&4";
		xxnf="echo \"there is no <\$1>, ...\" >&4";;
	esac;
done;
?X: Remaining values are set to 'undef'
while $test "$yyy";
do set $yyy; var=$2; eval "was=\$$2";
	eval "case \"\$$var\" in $define) . ./whoa; esac"; eval "$var=\$tu";
	set $yyy; shift; shift; yyy=$@;
done'