Data update

Task/Call-a-foreign-language-function/Pluto/call-a-foreign-language-function-1.pluto

@@ -0,0 +1,18 @@
+/* mylib.c */
+
+// gcc -c -fpic mylib.c
+// gcc -shared -o mylib.so mylib.o
+
+#include <string.h>
+#include <stdlib.h>
+
+static void *strptr = NULL;
+
+extern char *my_strdup(const char *src) {
+    strptr = (void *)strdup(src);
+    return (char *)strptr;
+}
+
+extern void my_free() {
+    free(strptr);
+}

Task/Call-a-foreign-language-function/Pluto/call-a-foreign-language-function-2.pluto

@@ -0,0 +1,10 @@
+local ffi = require "pluto:ffi"
+local lib = ffi.open("./mylib.so")
+lib:cdef[[
+    char *my_strdup(const char *src);
+    void my_free();
+]]
+local s = "Hello World!"
+print(lib.my_strdup(s))
+lib.my_free()
+lib = nil