Add a small makefile to build popen_noshell as a static lib

.gitignore

@@ -25,3 +25,6 @@ kpvcrlib/CMakeCache.txt
 kpvcrlib/CMakeFiles/
 kpvcrlib/cmake_install.cmake
 kpvcrlib/Makefile
+
+popen-noshell/libpopen_noshell.a
+popen-noshell/*.o

popen-noshell/Makefile

@@ -0,0 +1,15 @@
+SRCS=popen_noshell.c
+
+OBJS:=$(SRCS:%.c=%.o)
+
+%.o: %.c
+	$(CC) $(CPPFLAGS) $(CFLAGS) -o $@ -c $<
+
+all: libpopen_noshell.a
+
+libpopen_noshell.a: $(OBJS)
+	$(AR) rcs $@ $(OBJS)
+
+clean:
+	rm -rf *.o
+	rm -rf libpopen_noshell.a