lseek

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    LSEEK(2)            Linux Programmer's Manual            LSEEK(2)

    NAME
           lseek - reposition read/write file offset

    SYNOPSIS
           #include <unistd.h>

           off_t lseek(int fildes, off_t offset, int whence);

    DESCRIPTION
           The  lseek  function  repositions  the  offset of the file
           descriptor fildes to the argument offset according to  the
           directive  whence.   The  argument  fildes must be an open
           file  descriptor.   Lseek  repositions  the  file  pointer
           fildes as follows:

                  If  whence is SEEK_SET, the offset is set to offset
                  bytes.

                  If whence is SEEK_CUR, the offset  is  set  to  its
                  current location plus offset bytes.

                  If  whence  is  SEEK_END,  the offset is set to the
                  size of the file plus offset bytes.

           The lseek function allows the file offset to be set beyond
           the  end  of the existing end-of-file of the file. If data
           is later written at this point, subsequent  reads  of  the
           data in the gap return bytes of zeros (until data is actu-
           ally written into the gap).

           Some devices are incapable of seeking.  The value  of  the
           pointer associated with such a device is undefined.

    RETURN VALUES
           Upon  successful  completion,  lseek returns the resulting
           offset location as measured in bytes from the beginning of
           the  file.  Otherwise, a value of -1 is returned and errno
           is set to indicate the error.

    ERRORS
           EBADF  Fildes is not an open file descriptor.

           ESPIPE Fildes is associated with a pipe, socket, or  FIFO.

           EINVAL Whence is not a proper value.

    CONFORMS TO
           POSIX, BSD 4.3

    BUGS
           This  document's  use  of whence is incorrect English, but
           maintained for historical reasons.

    Linux 1.2.9                10 June 1995                         1

    LSEEK(2)            Linux Programmer's Manual            LSEEK(2)

### SEE ALSO

dup, open, fseek,

###

    Linux 1.2.9                10 June 1995                         2

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