[libk]: libk补交 unistd

src/include/unistd.h

@@ -0,0 +1,13 @@
+#ifndef UNISTD_H
+#define UNISTD_H
+
+// #include "../../include/unistd.h"
+//
+// extern char **__environ;
+//
+// hidden int __dup3(int, int, int);
+// hidden int __mkostemps(char *, int, int);
+// hidden int __execvpe(const char *, char *const *, char *const *);
+// hidden off_t __lseek(int, off_t, int);
+
+#endif