SEEK(II) 8/5/73 SEEK(II)
NAME
seek - move read/write pointer
SYNOPSIS
(seek = 19.)
(file descriptor in r0)
sys seek; offset; ptrname
seek(fildes, offset, ptrname)
DESCRIPTION
The file descriptor refers to a file open for reading or
writing. The read (resp. write) pointer for the file is set
as follows:
if ptrname is 0, the pointer is set to offset.
if ptrname is 1, the pointer is set to its current loca-
tion plus offset.
if ptrname is 2, the pointer is set to the size of the
file plus offset.
if ptrname is 3, 4 or 5, the meaning is as above for 0, 1
and 2 except that the offset is multiplied by 512.
If ptrname is 0 or 3, offset is unsigned, otherwise it is
signed.
SEE ALSO
open(II), creat(II)
DIAGNOSTICS
The error bit (c-bit) is set for an undefined file descrip-
tor. From C, a -1 return indicates an error.
- 1 -