Veritas™ File System 5.0.1 Programmer's Reference Guide

vxfs_fcl_sync
The vxfs_fcl_sync function sets a synchronization point within the FCL file.
This function is kept for backward compatibility.
Before the availability of the VxFS 5.0 API to access the FCL file, applications
would typically call vxfs_fcl_sync to get the FCL to a stable state and set an
offset in the FCL file to use as a reference point to stop reading. The application
would then store the offset and use it to determine files changes since the last
FCL read time. A vxfs_fcl_sync call ensured that if a file had been written to or
opened, there would be at least one corresponding write or open record in the FCL
after the synchronization offset. This would happen even if the time specified by
fcl_winterval or fcl_ointerval had not elapsed since the last record was written.
With the VxFS 5.0 API FCL access, synchronization is now done automatically
when the FCL file is opened through vxfs_fcl_open. The vxfs_fcl_open function
sets a synchronization point and determines a reference end offset internally.
Parameters
The following is the syntax for the vxfs_fcl_sync function:
int vxfs_fcl_sync(char *fname, uint64_t *offp);
The function parameters are as follows:
■ *fname is a pointer to the FCL filename
■ *offp is the address of a 64-bit offset
vxfs_fcl_sync brings the FCL file to a stable state and updates *offp with an
offset that can be used by the application as a reference point.
File Change Log record
An application reads the FCL file through the vxfs_fcl_read function.
vxfs_fcl_read performs the following tasks:
■ Reads the data from the FCL file
■ Assembles the data into fcl_record structures
■ Fills the buffer passed in by the application with these records
Each fcl_record structure represents a logical event recorded in the FCL. It is
defined as the following:
struct fcl_record {
uint32_t fr_reclen; /* Record length */
File Change Log
Application programming interface for File Change Log
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