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32 .\" @(#)lseek.2 8.3 (Berkeley) 4/19/94
33 .\" $FreeBSD: src/lib/libc/sys/lseek.2,v 1.10.2.6 2001/12/14 18:34:01 ru Exp $
40 .Nd reposition read/write file offset
46 .Fn lseek "int fildes" "off_t offset" "int whence"
50 function repositions the offset of the file descriptor
55 according to the directive
62 repositions the file position pointer associated with the file
66 .Bl -item -offset indent
80 the offset is set to its current location plus
88 the offset is set to the size of the
96 function allows the file offset to be set beyond the end
97 of the existing end-of-file of the file.
98 If data is later written
99 at this point, subsequent reads of the data in the gap return
100 bytes of zeros (until data is actually written into the gap).
102 Some devices are incapable of seeking. The value of the pointer
103 associated with such a device is undefined.
105 Upon successful completion,
107 returns the resulting offset location as measured in bytes from the
108 beginning of the file.
110 a value of -1 is returned and
116 will fail and the file position pointer will remain unchanged if:
120 is not an open file descriptor.
123 is associated with a pipe, socket, or FIFO.
126 is not a proper value.
132 This document's use of
134 is incorrect English, but is maintained for historical reasons.
138 function call is expected to conform to
143 function call appeared in