1 files changed, 18 insertions, 0 deletions
diff --git a/include/ruby/ruby.h b/include/ruby/ruby.h
index eb9a7e4d0f..0c1e1c2a6e 100644
--- a/include/ruby/ruby.h
+++ b/include/ruby/ruby.h
@@ -270,6 +270,24 @@ RBIMPL_ATTR_FORMAT(RBIMPL_PRINTF_FORMAT, 3, 0)
  */
 int ruby_vsnprintf(char *str, size_t n, char const *fmt, va_list ap);
 
+// TODO: doc
+
+#include <errno.h>
+
+int rb_errno(void);
+void rb_errno_set(int);
+int *rb_errno_ptr(void);
+
+static inline int *
+rb_orig_errno_ptr(void)
+{
+    return &errno;
+}
+
+#define rb_orig_errno errno
+#undef errno
+#define errno (*rb_errno_ptr())
+
 /** @cond INTERNAL_MACRO */
 #if RBIMPL_HAS_WARNING("-Wgnu-zero-variadic-macro-arguments")
 # /* Skip it; clang -pedantic doesn't like the following */