DosQueryVerify

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Determines if write verification is enabled.

Syntax

DosQueryVerify(pBool)

Parameters

pBool (PBOOL32) - output 
Address of the verify mode for the process.
Possible values are shown in the list below:
0 Verify mode is not active.
1 Verify mode is active.

Return Code

ulrc (APIRET) - returns
DosQueryVerify returns one of the following value:
  • 0 NO_ERROR

Remarks

When the verify mode is active, the operating system verifies that data written to the disk is recorded correctly, even though disk recording errors are rare.

Example Code

This example enables disk write verification, and then creates and writes to a file named "VERIFY.DAT". It restores the original setting when it finishes.

#define INCL_DOSFILEMGR          /* File Manager values */
#define INCL_DOSERRORS           /* DOS Error values    */
#include <os2.h>
#include <stdio.h>
#include <string.h>

int main(VOID) {
   UCHAR  uchFileName[20]  = "VERIFY.DAT",     /* Name of file to use      */
          uchFileData[10] = "SampleData";      /* Stuff to put in file     */
   HFILE  hfFileHandle   = 0L;                 /* Handle for user file     */
   BOOL32 fUserVerify    = 0;                  /* User Verify flag setting */
   ULONG  ulAction       = 0,                  /* Action done by DosOpen   */
          ulWritten      = 0;                  /* Number of bytes written  */
   APIRET rc             = NO_ERROR;           /* Return code              */

   rc = DosQueryVerify(&fUserVerify);     /* Get current setting of VERIFY */
   if (rc != NO_ERROR) {
     printf("DosQueryVerify error: return code = %u\n", rc);
     return 1;
   } else {
     printf ("Original setting of Verify=%s\n",(fUserVerify) ? "On" : "Off");
   } /* endif */

   rc = DosSetVerify(1);                  /* Set VERIFY=ON                 */
   if (rc != NO_ERROR) {
     printf("DosSetVerify error: return code = %u\n", rc);
     return 1;  }

   /* Open the file VERIFY.DAT for read/write.  Create it if necessary */

   rc = DosOpen(uchFileName, &hfFileHandle, &ulAction,
                10L, FILE_NORMAL,
                OPEN_ACTION_CREATE_IF_NEW | OPEN_ACTION_OPEN_IF_EXISTS,
                OPEN_SHARE_DENYNONE  | OPEN_ACCESS_READWRITE, 0L);

   if (rc != NO_ERROR) {
      printf("DosOpen error: return code = %u\n", rc);
      return 1; }

         /* Write critical data to the file */

   rc = DosWrite (hfFileHandle, (PVOID) uchFileData,
                  sizeof(uchFileData), &ulWritten);
   if (rc == NO_ERROR) {
      printf ("%u bytes written to file %s with Verify=On\n",
               ulWritten,uchFileName);
   }
   rc = DosSetVerify(fUserVerify);         /* Restore user's verify value */
   if (rc != NO_ERROR) {
     printf("DosSetVerify error: return code = %u\n", rc);
     return 1;
   }

   rc = DosClose(hfFileHandle);            /* Close the file              */

   return NO_ERROR;
}

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