【提问】QT如何锁一个文件,不让其它程序读或者写?? [复制链接]

Header File
io.h
Category
Input/output Routines
Prototype
int lock(int handle, long offset, long length);
Description
Sets file-sharing locks.
lock provides an interface to the operating system file-sharing mechanism.
A lock can be placed on arbitrary, nonoverlapping regions of any file. A program attempting to read or write into a locked region will retry the operation three times. If all three retries fail, the call fails with an error.
Return Value
lock returns 0 on success. On error, lock returns -1 and sets the global variable errno to
EACCES      Locking violation

#include <io.h>
#include <fcntl.h>
#include <sys\stat.h>
#include <process.h>
#include <share.h>
#include <stdio.h>
int main(void)
{
  int handle, status;
  long length;
  handle = _sopen("c:\\autoexec.bat",
    O_RDONLY,SH_DENYNO,S_IREAD);
  if (handle < 0)
  {
    printf("_sopen failed\n");
    exit(1);
  }
  length = filelength(handle);
  status = lock(handle,0L,length/2);
  if (status == 0)
    printf("lock succeeded\n");
  else
    printf("lock failed\n");
  status = unlock(handle,0L,length/2);
  if (status == 0)
    printf("unlock succeeded\n");
  else
    printf("unlock failed\n");
  close(handle);
  return 0;
}