Format
#include <recio.h>
#include <xxfdbk.h>
_XXIOFB_T *_Riofbk(_RFILE *fp);Language Level: ILE C Extension
Threadsafe: Yes.
Description
The _Riofbk() function returns a pointer to a copy of the I/O feedback area for the file that is specified by fp.
The _Riofbk() function is valid for all types of files.
Return Value
The _Riofbk() function returns NULL if an error occurs. See Table 12 and Table 14 for errno settings.
Example that uses _Riofbk()
#include <stdio.h>
#include <recio.h>
#include <string.h>
#include <stdlib.h>
typedef struct {
char name[20];
char address[25];
} format1 ;
typedef struct {
char name[8];
char password[10];
} format2 ;
typedef union {
format1 fmt1;
format2 fmt2;
} formats ;
int main(void)
{
_RFILE *fp; /* File pointer */
_RIOFB_T *rfb; /*Pointer to the file's feedback structure */
_XXIOFB_T *iofb; /* Pointer to the file's feedback area */
formats buf, in_buf, out_buf; /* Buffers to hold data */
/* Open the device file. */
if (( fp = _Ropen ( "MYLIB/T1677RD2", "ar+" )) == NULL )
{
printf ( "Could not open file\n" );
exit ( 1 );
}
_Racquire ( fp,"DEVICE1" ); /* Acquire another device. Replace
*/
/* with actual device name. */
_Rformat ( fp,"FORMAT1" ); /* Set the record format for the */
/* display file. */
rfb = _Rwrite ( fp, "", 0 ); /* Set up the display. */
_Rpgmdev ( fp,"DEVICE2" ); /* Change the default program device. */
/* Replace with actual device name. */
_Rformat ( fp,"FORMAT2" ); /* Set the record format for the */
/* display file. */
rfb = _Rwrite ( fp, "", 0 ); /* Set up the display. */
rfb = _Rwriterd ( fp, &buf, sizeof(buf) );
rfb = _Rwrread ( fp, &in_buf, sizeof(in_buf), &out_buf,
sizeof(out_buf ));
_Rreadindv ( fp, &buf, sizeof(buf), __DFT );
/* Read from the first device that */
/* enters data - device becomes */
/* default program device. */
/* Determine which terminal responded first. */
iofb = _Riofbk ( fp );
if ( !strncmp ( "FORMAT1 ", iofb -> rec_format, 10 ))
{
_Rrelease ( fp, "DEVICE1" );
}
else
{
_Rrelease(fp, "DEVICE2" );
}
/* Continue processing. */
printf ( "Data displayed is %45.45s\n", &buf);
_Rclose ( fp );
}Related Information