user: implement mlibc as the libc, finally.

It's finally done..

Signed-off-by: kaguya <vpshinomiya@protonmail.com>

user/include/mlibc/tests/linux/process_vm_readv_writev.c

@@ -0,0 +1,35 @@
+#include <assert.h>
+#include <stdio.h>
+#include <sys/uio.h>
+#include <unistd.h>
+
+// Test variable to read and write
+static int test = 42;
+
+int main() {
+	// Read the variable using process_vm_readv
+	int temp;
+	struct iovec local_iov = {
+		.iov_base = &temp,
+		.iov_len = sizeof(temp),
+	};
+	struct iovec remote_iov = {
+		.iov_base = &test,
+		.iov_len = sizeof(test),
+	};
+	ssize_t bytes_read = process_vm_readv(getpid(), &local_iov, 1, &remote_iov, 1, 0);
+	assert(bytes_read == sizeof(test));
+	assert(temp == 42);
+
+	// Write a new value to the variable using process_vm_writev
+	int new_value = 1337;
+	struct iovec new_local_iov = {
+		.iov_base = &new_value,
+		.iov_len = sizeof(new_value),
+	};
+	ssize_t bytes_written = process_vm_writev(getpid(), &new_local_iov, 1, &remote_iov, 1, 0);
+	assert(bytes_written == sizeof(new_value));
+	assert(test == 1337);
+
+	return 0;
+}