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X-Hacker.org- GT_LIB v1.0 Reference Guide Release 1.0 - <b>unlock a region of a low level file.</b>
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Unlock a region of a low level file.
------------------------------------------------------------------------------
Syntax
GT_FUnLock(<nHandle>,<nOffset>,<nLength>) --> lUnLocked
Arguments:
<nHandle> is a numeric file handle.
<nOffset> is the byte position at which the unlock will start. This
is a zero based value.
<nLength> is the length of the region to unlock.
Returns:
A logical value, .T. if the region was unlocked, .F. if not.
Description:
GT_FUnLock() can be used to unlock a region of a low level file
that has been locked withg GT_FLock().
To use the low-level locking/un-locking functions you will first
need to open the file with fopen(), or perhaps create a file with
fcreate(). Once open you can use the file handle returned by
Clipper to carry out a lock.
Examples:
#include "fileio.ch"
if (nFile := fopen("LIFE.42",FO_SHARED)) != F_ERROR
// Lock a region in the file at position 10 (don't forget,
// the offset starts at 0, not 1!
if GT_FLock(nFile,10,2)
// Make some changes to the file.
.
.
.
// Now unlock the same region.
GT_FUnLock(nFile,10,2)
endif
fclose(nFile)
endif
Source: LLFLOCK.C
Author: Dave Pearson
See Also: GT_FLOCK()
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