Format
#include <recio.h>
_RIOFB_T *_Rupfb(_RFILE *fp);Language Level: ILE C Extension
Threadsafe: Yes. However, if the file pointer is passed among threads, the I/O feedback area is shared among those threads.
Description
The _Rupfb() function updates the feedback structure associated with the file specified by fp with information about the last I/O operation. The _RIOFB_T structure will be updated even if riofb=N was specified when the file was opened. The num_bytes field of the _RIOFB_T structure will not be updated. See <recio.h> for a description of the _RIOFB_T structure.
The _Rupfb() function is valid for all types of files.
Return Value
The _Rupfb() function returns a pointer to the _RIOFB_T structure specified by fp. See Table 12 and Table 14 for errno settings.
Example that uses _Rupfb()
#include <stdio.h>
#include <recio.h>
#include <stdlib.h>
int main(void)
{
_RFILE *fp;
_RIOFB_T *fb;
/* Create a physical file */
system("CRTPF FILE(QTEMP/MY_FILE) RCDLEN(80)");
/* Open the file for write */
if ( (fp = _Ropen("QTEMP/MY_FILE", "wr")) == NULL )
{
printf("open for write fails\n");
exit(1);
}
/* Write some records into the file */
_Rwrite(fp, "This is record 1", 16);
_Rwrite(fp, "This is record 2", 16);
_Rwrite(fp, "This is record 3", 16);
_Rwrite(fp, "This is record 4", 16);
_Rwrite(fp, "This is record 5", 16);
_Rwrite(fp, "This is record 6", 16);
_Rwrite(fp, "This is record 7", 16);
_Rwrite(fp, "This is record 8", 16);
_Rwrite(fp, "This is record 9", 16);
/* Close the file */
_Rclose(fp);
/* Open the file for read */
if ( (fp = _Ropen("QTEMP/MY_FILE", "rr, blkrcd = y")) == NULL )
{
printf("open for read fails\n");
exit(2);
}
/* Read some records */
_Rreadn(fp, NULL, 80, __DFT);
_Rreadn(fp, NULL, 80, __DFT);
/* Call _Rupfb and print feed back information */
fb = _Rupfb(fp);
printf("record number -------------------------- %d\n",
fb->rrn);
printf("number of bytes read ------------------- %d\n",
fb->num_bytes);
printf("number of records remaining in block --- %hd\n",
fb->blk_count);
if ( fb->blk_filled_by == __READ_NEXT )
{
printf("block filled by ------------------------ __READ_NEXT\n");
}
else
{
printf("block filled by ------------------------ __READ_PREV\n");
}
/* Close the file */
_Rclose(fp);
}Related Information