Comparing characters

Hello,

I am currently new to both this board and to C programming. What I am attempting to do, is to compare a character to another one.

This is done by:

Code:

---

char vowels[] = "aeiouyæøå";

int isVowel(char c)
{
  int i;
  for(i = 0; i < strlen(vowels); i++) if(strcmp(tolower(c), vowels[i]) == 0) return 1;
  return 0;
}

// Several other irrelevant lines of code
// I have some lines of a song saved in char *lines[NO_LINES]
// where NO_LINES is defined to 4.
// The call of isVowel from the function rem:

int rem(void)
{
  int i;
  for(i = 0; i < NO_LINES; i++)
  {
    int j;
    for(j = 0; j < strlen(lines[i]); j++)
    {
      if(isVowel((char)lines[i][j]) == 0) printf("%c", lines[i][j]);
    }
  }
  return 1;
}

---

I try merrily to compile this, and I get some warnings:

Code:

---

$ cc o1.c
o1.c: In function 'isVowel':
o1.c:17: warning: passing argument 1 of 'strcmp' makes pointer from integer without a cast
o1.c:17: warning: passing argument 2 of 'strcmp' makes pointer from integer without a cast

---

And when I try to run the program, I get:

Code:

---

$ ./a.out remove tresmaa.txt
Bus error

---

remove is an argument to start rem(), and lines[] is filled with 4 lines from before rem()'s call. I have tried to debug this, and it is the strcmp(tolower(c), vowels[i]) call that causes the problem. I have ensured that I have included all necessary headers, but I cannot see why I get this bus error. Thus I would be more than happy if I could get some help from you. :)

Thanks in advance and best regards,

Thuz

strcmp is used to compare strings; to compare characters, just compare characters.

Code:

---

char vowels[] = "aeiouyæøå";

int isVowel(char c)
{
  int i;
  for ( i = 0; vowels[i] != '\0'; i++ )
  {
      if ( tolower(c) == vowels[i] )
      {
        return 1;
      }
  }
  return 0;
}

---

That worked wonders. Silly of me not to be thinking of that easy and correct solution. :)

Thank you very much for your help Dave.