Positions the file mark before reading from or writing to an open file.

OSErr PBSetFPosSync (
    ParmBlkPtr paramBlock
);

paramBlock

A pointer to a basic File Manager parameter block.

function result

A result code.

DISCUSSION

The relevant fields of the parameter block are:

• ioCompletion

  On input, a pointer to a completion routine.

• ioResult

  On output, the result code of the function.

• ioRefNum

  On input, the file reference number for the file whose mark you wish to set.

• ioPosMode

  On input, the positioning mode

• ioPosOffset

  On input, the positioning offset. On output, the position at which the mark was actually set.

The PBSetFPosSync function sets the mark of the specified file to the position specified by the ioPosMode and ioPosOffset fields. If you try to set the mark past the logical end-of-file, PBSetFPosSync moves the mark to the end-of-file and returns eofErr as its function result.

AVAILABILITY

Supported in Carbon. Available in Mac OS 8.1 and later when Carbon 1.0.2 or later is present.

© 2000 Apple Computer, Inc. — (Last Updated 5/8/2000)