Implemented echo example

lib/mem/alloc.q

@@ -0,0 +1,9 @@
+import sys
+
+alloc(length) {
+	return sys.mmap(0, length, 3, 290)
+}
+
+free(address, length) {
+	return sys.munmap(address, length)
+}

lib/sys/linux.q

@@ -3,7 +3,7 @@ read(fd, address, length) {
 }
 
 write(fd, address, length) {
-	syscall(1, fd, address, length)
+	return syscall(1, fd, address, length)
 }
 
 open(file, flags, mode) {