Issue in printf statement

[Dora ji]

Hi,

I am trying to call db2 in C on zos.Actually the program is fetching the data from the table.But it is not printing the output in the printf statement.
Hereby i have given the part of the code.

Code: Select all

#include<stdio.h>
.
.
.
{
printf("*** Cursor Declaration  ***\n");

     EXEC SQL DECLARE C1 CURSOR FOR
    SELECT
    DEPTNUM
    FROM
    STDDATA
    WHERE
    STDID = 10
    ;

    EXEC SQL OPEN C1;

  printf("After OPEN Cursor C1 SQLERROR CODE(%d)\n",sqlcode);
  printf("Fetch Cursor");

  if(sqlca.sqlcode < 0) {return -1;}

      EXEC SQL FETCH C1 INTO
      :S_DEPTNUM;
      returncode = sqlcode;

  printf("After FETCH Cursor C1 SQLERROR CODE(%d)\n",sqlcode);

  printf("DEPTNUM IS:\n",S_DEPTNUM);     <-- error here

 printf("\n***   Successful   ***\n");
}

S_DEPTNUM is the host variable i declared in the program.
The printf statement which i bolded doesn't display a result.It displays only the statement which is under quotes.Do the printf statement is correct??.
I need that the fetched data should move into the host variables and it is to be displayed in spool.
Kindly please share your views to make the code successful.

Coded

[NicC]

How about coding a format string for s_deptnum in your printf string?
How about using the code tags for presenting your code in a user friendly way?
Also, my understanding is that you should not use printf() unless there a minimum of 2 arguments - you shoud use puts(). This is because a printf() can be hacked - so I am told by "Deitel & Deitel"

[Dora ji]

Thanks Nicc..

Its working.

[awesome]

This is very nice and awesome post
I like it very much
Thanks alot...

[enrico-sorichetti]

Also, my understanding is that you should not use printf() unless there a minimum of 2 arguments - you shoud use puts(). This is because a printf() can be hacked - so I am told by "Deitel & Deitel"

I humbly beg to differ

printf with one argument is unsafe only for a non literal format string

Code: Select all


#include "stdio.h"
int main()
{
   int data =1;
   char *fmt  = "pointer based format  only\n";
   char *fmtd = "pointer based format  and data %d\n";

   printf(fmt);
   printf(fmtd, data);

   printf("constant      format  only\n");
   printf("constant      format  and data %d\n", data) ;

   return 0;

}


Code: Select all

[enrico@enrico-imac tests]$cc z.c
z.c:12:9: warning: format string is not a string literal (potentially insecure) [-Wformat-security]
        printf(fmt);
               ^~~
1 warning generated.


Code: Select all

[enrico@enrico-imac tests]$./a.out
pointer based format  only
pointer based format  and data 1
constant      format  only
constant      format  and data 1
[enrico@enrico-imac tests]$

same warning for c++

[NicC]

Why didn't you say so at the time, Enrico?! This topic is almost a year old so it is that amount of time since I was reading the book - still not finished so still learning basics.

[enrico-sorichetti]

Hello Nic
the topic just came out when clicking on NEW POSTS

by awesome » Fri Apr 24, 2015 8:46 am

so I just replied without looking at the conversation flow

c /one year/two years/