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Annotation of cci/usr/src/man/man2/lseek.2, revision 1.1.1.2

1.1       root        1: .TH LSEEK 2 "7 July 1983"
                      2: .UC 4
                      3: .SH NAME
                      4: lseek \- move read/write pointer
                      5: .SH SYNOPSIS
                      6: .nf
                      7: .ft B
                      8: .ta 1.25i 1.6i
                      9: #define L_SET  0       /* set the seek pointer */
                     10: #define L_INCR 1       /* increment the seek pointer */
                     11: #define L_XTND 2       /* extend the file size */
                     12: .PP
                     13: .ft B
                     14: pos = lseek(d, offset, whence)
                     15: int pos;
                     16: int d, offset, whence;
                     17: .fi
                     18: .ft R
                     19: .SH DESCRIPTION
                     20: The descriptor 
                     21: .I d
                     22: refers to a file or device open for reading and/or writing.
                     23: .I Lseek
                     24: sets the file pointer of
                     25: .I d
                     26: as follows:
                     27: .IP
                     28: If
                     29: .I whence
                     30: is L_SET, the pointer is set to
                     31: .I offset
                     32: bytes.
                     33: .IP
                     34: If
                     35: .I whence
                     36: is L_INCR, the pointer is set to its current location plus
                     37: .IR offset .
                     38: .IP
                     39: If
                     40: .I whence
                     41: is L_XTND, the pointer is set to the size of the
                     42: file plus
                     43: .IR offset .
                     44: .PP
                     45: Upon successful completion, the resulting pointer location
                     46: as measured in bytes from beginning of the file is returned.
                     47: Some devices are incapable of seeking.  The value of the pointer
                     48: associated with such a device is undefined.
                     49: .SH NOTES
                     50: Seeking far beyond the end of a file, then writing,
                     51: creates a gap or \*(lqhole\*(rq, which occupies no
                     52: physical space and reads as zeros.
                     53: .SH "RETURN VALUE
                     54: Upon successful completion, a non-negative integer,
                     55: the current file pointer value, is returned.  Otherwise,
                     56: a value of \-1 is returned and \fIerrno\fP is set to indicate
                     57: the error.
                     58: .SH "ERRORS
                     59: .I Lseek
1.1.1.2 ! root       60: fails and the file pointer remains unchanged if:
1.1       root       61: .TP 15
                     62: [EBADF]
                     63: .I Fildes
                     64: is not an open file descriptor.
                     65: .TP 15
                     66: [ESPIPE]
                     67: .I Fildes
                     68: is associated with a pipe or a socket.
                     69: .TP 15
                     70: [EINVAL]
                     71: .I Whence
                     72: is not a proper value.
                     73: .TP 15
                     74: [EINVAL]
                     75: The resulting file pointer would be negative.
                     76: .SH "SEE ALSO"
                     77: dup(2), open(2)
                     78: .SH BUGS
                     79: This document's use of
                     80: .I whence
                     81: is incorrect English, but maintained for historical reasons.

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