Thread: Reading const char array via scanf

Hello, I am trying to read an input which has "cont char" type. Once I enter the first input, it gives the error at the end of the thread below my code. What am I missing here?

Code:

  #include <stdio.h>
    int main (void)
    {
        int d;
        int ChnCount =4;
                const char physicalChannel[ChnCount];
        for (d=0; d<ChnCount; d++)
          {
        printf(" Enter the ID no. (0 to 7) for channel %d of %d \n: ",d+1, ChnCount);   /*------------*/
           scanf("Dev1/ai %s", &physicalChannel[d]); 
        }
        for (d=0; d<ChnCount; d++)
        {
        printf ("%s\n", physicalChannel[d]);
        }
    return 0;
    }

I see this on the screen after entering the first input. The errors are:
1. it doesnt ask me for channels 2,3 and 4.
2. it doesnt print physicalChannel[d].

Code:

 Enter the ID no. (0 to 7) for channel 1 of 4: 1
 Enter the ID no. (0 to 7) for channel 2 of 4:  Enter the ID no. (0 to 7) for channel 3 of 4:  Enter the ID no. (0 to 7) for channel 4 of 4:

Cheers!

what loops does what? inner loops runs how many times before the outer loop runs again?

Code:

#include <stdio.h>

int main(void)
{
int a,b, something;

 for ( a = 0; a<4; a++)
{
   for (b = 0; b < 1; b++)
    {
      printf("enter something\n");
      scanf("%d", &something);
    }
   printf("something = %d\n", something);
}

return 0;
}

Code:

#include <stdio.h>

int main(void)
{
char a1, a2, a3, a4;
printf("enter 4 somethings\n");
scanf("%c %c %c %c", &a1,&a2,&a3,&a4);
printf("something = %c  %c %c %c\n",a1,a2,a3,a4);
return 0;
}

Originally Posted by cyln

Sorry this doesn't answer my question

Code:

char d[3];

how every you write that to give it is length. will only be good for one word size of length - 1 for end char '\0' .

your scanf is only good for one input it will not stop and wait for another one. chars are tricky, you cannot put 4 separate answers in that one char like that. it is length of a word.

Code:

printf(" inpout 4 chanl\n")
 scanf("%s", ch1);
 scanf("%s", ch2);
 scanf("%s", ch3);
 scanf("%s", ch4);

I see your logic but it is not going to work like that.
loops are pretty much out.
that is why I showed you how to get 4 off the command line off the bat or write it 4 times.

Code:

#include <stdio.h>
  int main (void)
  {
     
  char d[] = "hello";
   printf ("%s\n", d); 
   printf("%c\n",d[2]);
 
  return 0;
  }

output

Code:

[userx@void bin]$ gcc loopy.c
[userx@void bin]$ ./a.out
hello
l

C Strings (Arrays vs. Pointers)