Our 'install-sh' script is BSD-style, therefore requires -c

to behave sanely.  configure was not treating it as BSD...

src/configure

@@ -1407,7 +1407,7 @@ case "$host_os" in
 esac
 
 case "`basename $INSTALL`" in
- install|installbsd|scoinst)
+ install|installbsd|scoinst|install-sh)
 	INSTLOPTS="-c $INSTLOPTS"
 	INSTL_EXE_OPTS="-c $INSTL_EXE_OPTS"
 	INSTL_LIB_OPTS="-c $INSTL_LIB_OPTS"

src/configure.in

@@ -373,8 +373,10 @@ case "$host_os" in
 	INSTL_SHLIB_OPTS="-m 555" ;;
 esac
 
+dnl These flavors of install need -c to install by copy rather than move.
+dnl install by move is fatal because it removes stuff from the source tree!
 case "`basename $INSTALL`" in
- install|installbsd|scoinst)
+ install|installbsd|scoinst|install-sh)
 	INSTLOPTS="-c $INSTLOPTS"
 	INSTL_EXE_OPTS="-c $INSTL_EXE_OPTS"
 	INSTL_LIB_OPTS="-c $INSTL_LIB_OPTS"