create the shell loop

Makefile

@@ -1,13 +1,14 @@
 CC=clang
-CFLAGS=-Wall -Isrc/include -DDEBUG -g
-LDFLAGS=-lm
-SRC=src/myshellin.c
+CFLAGS=-Wall -Isrc/include -DDEBUG -g -std=c17
+LDFLAGS=
+FILENAME=myshellin
+SRC=src/myshellin.c src/loop.c
 OBJ=$(SRC:.c=.o)
 
-all: myshellin informe
+all: myshellin
 
 myshellin: $(OBJ)
-	$(CC) -o $@ $^ $(LDFLAGS)
+	$(CC) $(CFLAGS) -o $(FILENAME) $^ $(LDFLAGS)
 
 informe:
 # if pdflatex is installed create the informe
@@ -16,7 +17,7 @@ ifneq (, $(shell which pdflatex))
 	mv doc/Informe.pdf Informe.pdf
 endif
 
-clean: cleanmyshellin cleaninforme
+clean: cleanmyshellin
 
 cleanmyshellin:
 	rm -f src/*.o myshellin

src/include/loop.h

@@ -0,0 +1,2 @@
+void print_input_line();
+void loop();

src/loop.c

@@ -0,0 +1,18 @@
+#define _GNU_SOURCE
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+
+void print_input_line() {
+    printf("$ ");
+}
+
+void loop() {
+    size_t buffer_size = 0;
+    char *line = NULL;
+
+    while (1) {
+        print_input_line();
+        getline(&line, &buffer_size, stdin);
+    }
+}

src/myshellin.c

@@ -1,5 +1,6 @@
-int main(int argc, char **argv)
-{
+#include "loop.h"
 
+int main(int argc, char **argv) {
+    loop();
     return 0;
 }