String functions in C?

Lakshit

I'm attempting to make my own string function and I am by all accounts stuck as of now. The following is what I have such a long way to make a string and print it and return the size. Yet, I really want to make a function that is passed the pointer to a string of chars as well as a char and it returns the number of occurrences of that char in the string. I am trying to call the function make_string from this function but can't get it to work. The .h file just has the functions pre-listed.

#include "readLineUtilities.h"

int make_string(char **line)
{
char *a,b;
int i,size=0;
a = (char *) malloc(sizeof(char));
b = getchar();
while( b != '\n' && size < MAX)
{       
    *(a+size) = b;  //remember at this point size = 0
    size++;
    b = getchar();
    a = realloc(a,size+1);
}
*(a+size) = '\0';  //end of string marker so no need to return the size directly
*line = a;
return size;    

}

int char_in_string (char *line, char c) {

make_string(*line);

}

void print_string(char *line, int size){
char *a;
int i;
a = line;
for (i=0;i<size;i++)
    printf("%c",*(a+i)); //no end of line
printf("\n");
}


int length_string(char *line){
int size = 0;
char *c,b;
c = line;
if ( c == NULL){ 
    printf("line is null\n");
    return size;
}
while (*(c + size) != '\0'){
    size++;
}
return size;
}

I want to try the procedure described here but I'm scared if I tried wrong. Can someone give some insight here? Any help with this problem would be appreciated. Much Thanks!