add -P pkgdir option to 6l to have it look first in pkgdir for a package.

this allows gotest to find the locally built package when doing
	make
	gotest
without this option, one would have to say
	make install
	gotest
which kinda defeats the purpose

based on discussions with rsc.

R=ken,rsc
DELTA=12  (10 added, 1 deleted, 1 changed)
OCL=27606
CL=27606

1 files changed, 9 insertions, 2 deletions

diff --git a/src/cmd/6l/obj.c b/src/cmd/6l/obj.c
index 3a4208cd22..b65c7f313b 100644
--- a/src/cmd/6l/obj.c
+++ b/src/cmd/6l/obj.c
@@ -87,6 +87,7 @@ main(int argc, char *argv[])
 	INITDAT = -1;
 	INITRND = -1;
 	INITENTRY = 0;
+	PKGDIR = nil;
 
 	ARGBEGIN {
 	default:
@@ -122,6 +123,11 @@ main(int argc, char *argv[])
 		if(a)
 			INITRND = atolwhex(a);
 		break;
+	case 'P':
+		a = ARGF();
+		if(a)
+			PKGDIR = a;
+		break;
 	case 'x':	/* produce export table */
 		doexp = 1;
 		if(argv[1] != nil && argv[1][0] != '-' && !isobjfile(argv[1]))
@@ -684,9 +690,10 @@ addlib(char *src, char *obj)
 	}
 
 	if(search) {
-		// try dot and then try goroot.
-		// going to have to do better (probably a command line flag) later.
+		// try dot, -P "pkgdir", and then goroot.
 		snprint(pname, sizeof pname, ".%s", name);
+		if(access(pname, AEXIST) < 0 && PKGDIR != nil)
+			snprint(pname, sizeof pname, "%s/%s", PKGDIR, name);
 		if(access(pname, AEXIST) < 0)
 			snprint(pname, sizeof pname, "%s/pkg/%s", goroot, name);
 		strcpy(name, pname);