Example: Working with stream files

The program uses the following hierarchical file system (HFS) APIs:

• Create Directory (QHFCRTDR)
• Open Stream File (QHFOPNSF)
• Read from Stream File (QHFRDSF)
• Close Stream File (QHFCLOSF)

/********************************************************************/
/* Program Name:  HFSCOPY                                           */
/* Language    :  ILE C                                             */
/* Description :  This program will do the following:               */
/*                -- Create or replace a stream file                */
/*                -- Create or replace a database file              */
/*                -- Read from the stream file and write to the     */
/*                   database file until EOF                        */
/*                -- Close both files when done                     */
/* APIs Used   :  QHFCRTDR, QHFOPNSF, QHFRDSF, QHFCLOSF             */
/********************************************************************/

/********************************************************************/
/* Include files                                                    */
/********************************************************************/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <qhfopnsf.h>
#include <qhfrdsf.h>
#include <qhfclosf.h>
#include <qhfcrtdr.h>
#include <qusec.h>

/********************************************************************/
/* Structure and variable definitions                               */
/********************************************************************/

#define ON   1
#define OFF  0
typedef struct error_code_struct {
                Qus_EC_t EC;
                char exception_data[256];
               }error_code_struct;
error_code_struct error_code;
char file_handle[16];
char path_name[30];
char open_info[10];
char attrib_info;
char action;
char read_buffer[80];
int  path_length;
int  attrib_length = 0;
int  bytes_to_read;
int  bytes_read = 0;
int  end_file;
int  cmpgood;
FILE *FP;

/*********************************************************************/
/*printErrCode: Routine to print the error code structure            */
/*********************************************************************/
void printErrCode(error_code_struct *theErrCode)
{
   int i;
   char *tempptr = theErrCode->EC.Exception_Id;
   printf("Bytes Provided -> %d\n",theErrCode->EC.Bytes_Provided);
   printf("Bytes Available -> %d\n",theErrCode->EC.Bytes_Available);
   printf("Exception ID -> ");
   for (i=0;i<7 ;i++,tempptr++ )
     {
       putchar(*tempptr);
     }
   putchar('\n');
}


/********************************************************************/
/* Start of code                                                    */
/********************************************************************/
main()
{

 error_code.EC.Bytes_Provided = 116;
/********************************************************************/
/* Create the directory                                             */
/********************************************************************/
 strcpy(path_name,"/QDLS/HFSFLR");
 path_length = strlen(path_name);

 QHFCRTDR(path_name,path_length,&attrib_info,attrib_length,&error_code);
 if ( error_code.EC.Bytes_Available != 0 )
   {
    if (!memcmp(error_code.EC.Exception_Id,"CPF1F04",7))
       printf("Directory HFSFLR already created.\n");
    else
       {
        printErrCode(&error_code);
        exit(1);
       }
   }

/********************************************************************/
/* Open the stream file                                             */
/********************************************************************/
 strcpy(open_info,"210 120   ");    /* Create or replace the file   */
 strcpy(path_name,"/QDLS/HFSFLR/SAMPLE.HFS");
 path_length = strlen(path_name);
 printf("OPEN STREAM FILE:\n  ");
 QHFOPNSF(&file_handle,
          path_name,
          path_length,
          open_info,
          &attrib_info,
          attrib_length,
          &action,
          &error_code);
 if (error_code.EC.Bytes_Available != 0)
   {
    printErrCode(&error_code);
    exit(1);
   }

/********************************************************************/
/* Open a database file                                             */
/********************************************************************/
 system("CRTLIB LIB(HFSLIB)");
 if (( FP = fopen("HFSLIB/HFSFILE(SAMPLE)","wb")) == NULL)
   {
    printf("Cannot open HFSLIB/HFSFILE(SAMPLE)\n");
    exit(1);
   }

/********************************************************************/
/* Loop through reading from the stream file and writing to the     */
/* database file.                                                   */
/********************************************************************/

 end_file = OFF;
 while (end_file == OFF)
   {
     /*************************************************************/
     /* Read 80 bytes from the stream file                        */
     /*************************************************************/
     bytes_to_read = 80;
     printf("READ STREAM FILE:\n  ");
     QHFRDSF(&file_handle,
             read_buffer,
             bytes_to_read,
             &bytes_read,
             &error_code);
     if (error_code.EC.Bytes_Available != 0)
       {
         cmpgood = strncmp("CPF1F33",error_code.EC.Exception_Id,7);
         if (cmpgood != 0)
           printErrCode(&error_code);
         end_file = ON;
       }
     else
       {
         printf("BYTES READ: %d\n  ",bytes_read);
         printf("READ BUFFER: %s\n",read_buffer);
         if (bytes_read < bytes_to_read)
           {
             end_file = ON;
             /*******************************************************/
             /* Write remaining bytes to the database file          */
             /*******************************************************/
             if (bytes_read > 0)
               fwrite(read_buffer,1,bytes_read,FP);
           }
       }
   }

/********************************************************************/
/* Close the stream file                                            */
/********************************************************************/
 printf("CLOSE STREAM FILE:\n  ");
 QHFCLOSF(&file_handle,
          &error_code);
 if (error_code.EC.Bytes_Available != 0)
   printErrCode(&error_code);

/********************************************************************/
/* Close the database file                                          */
/********************************************************************/
 fclose(FP);
}

To create the program using ILE C, specify the following:

CRTBNDC PGM(QGPL/HFSCOPY) SRCFILE(QGPL/QCSRC)