Index: uspace/lib/libc/include/errno.h
===================================================================
--- uspace/lib/libc/include/errno.h	(revision d3e69353929ddbf51ebfe9f5f9ddabbfceeec750)
+++ uspace/lib/libc/include/errno.h	(revision 04b687b4dcf35f4a93146301dcdccbddbce24f33)
@@ -36,4 +36,8 @@
 #define LIBC_ERRNO_H_
 
+/* TODO: support threads/fibrils */
+extern int _errno;
+#define errno _errno
+
 #include <kernel/errno.h>
 
Index: uspace/lib/libc/include/stdio.h
===================================================================
--- uspace/lib/libc/include/stdio.h	(revision d3e69353929ddbf51ebfe9f5f9ddabbfceeec750)
+++ uspace/lib/libc/include/stdio.h	(revision 04b687b4dcf35f4a93146301dcdccbddbce24f33)
@@ -53,4 +53,15 @@
 }
 
+typedef struct {
+	/** Underlying file descriptor. */
+	int fd;
+
+	/** Error indicator. */
+	int error;
+
+	/** End-of-file indicator. */
+	int eof;
+} FILE;
+
 extern int getchar(void);
 
@@ -71,4 +82,12 @@
 extern int rename(const char *, const char *);
 
+extern FILE *fopen(const char *, const char *);
+extern int fclose(FILE *);
+extern size_t fread(void *, size_t, size_t, FILE *);
+extern size_t fwrite(const void *, size_t, size_t, FILE *);
+extern int feof(FILE *);
+extern int ferror(FILE *);
+extern void clearerr(FILE *);
+
 #endif