kern: filedesc: Implement lseek() function

The lseek() function allows the call to resposition the file offset
using a specific whence value to govern offsetting semantics

Signed-off-by: Ian Moffett <ian@osmora.org>

1 files changed, 10 insertions, 0 deletions

diff --git a/src/sys/include/os/filedesc.h b/src/sys/include/os/filedesc.h
index a6a2ac5..b773de9 100644
--- a/src/sys/include/os/filedesc.h
+++ b/src/sys/include/os/filedesc.h
@@ -30,6 +30,7 @@
 #ifndef _OS_FILEDESC_H_
 #define _OS_FILEDESC_H_ 1
 
+#include <sys/seek.h>
 #include <sys/types.h>
 #include <os/vnode.h>
 
@@ -117,4 +118,13 @@ ssize_t write(int fd, const void *buf, size_t count);
  */
 ssize_t read(int fd, void *buf, size_t count);
 
+/*
+ * Reposition the file offset of a file
+ *
+ * @fd: File descriptor to reposition
+ * @offset: Offset to move `fd' to
+ * @whence: How it should be repositioned
+ */
+off_t lseek(int fd, off_t offset, int whence);
+
 #endif  /* !_OS_FILEDESC_H_ */