1LSEEK(2)                      System Calls Manual                     LSEEK(2)
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NAME

6       lseek, tell - move read/write pointer
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SYNOPSIS

9       long lseek(fildes, offset, whence)
10       long offset;
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12       long tell(fildes)
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DESCRIPTION

15       The  file descriptor refers to a file open for reading or writing.  The
16       read (resp. write) pointer for the file is set as follows:
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18              If whence is 0, the pointer is set to offset bytes.
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20              If whence is 1, the pointer is set to its current location  plus
21              offset.
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23              If  whence is 2, the pointer is set to the size of the file plus
24              offset.
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26       The returned value is the resulting pointer location.
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28       The obsolete function tell(fildes) is identical  to  lseek(fildes,  0L,
29       1).
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31       Seeking  far  beyond  the end of a file, then writing, creates a gap or
32       `hole', which occupies no physical space and reads as zeros.
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SEE ALSO

35       open(2), creat(2), fseek(3)
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DIAGNOSTICS

38       -1 is returned for an undefined file descriptor, seek  on  a  pipe,  or
39       seek to a position before the beginning of file.
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BUGS

42       Lseek is a no-op on character special files.
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ASSEMBLER

45       (lseek = 19.)
46       (file descriptor in r0)
47       sys lseek; offset1; offset2; whence
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49       Offset1  and  offset2  are  the high and low words of offset; r0 and r1
50       contain the pointer upon return.
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