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cpointerscharatoi

How to convert pointers from strtok to strings?

For example:

int main(){
char *str[4];
char data[]="abcd:3:4:5";
str[0]=strtok(data,":");
str[1]=strtok(NULL,":");
str[2]=strtok(NULL,":");
str[3]=strtok(NULL,":");
return 0;
}

On the input "abcd:3:4:5", a is a string and b c and d are integers. When I use strtok() the broken string is stored in 4 pointers (str[0] to str[3]), which are immutable. I need to store them in an array where I can change the integers afterwards. I would use atoi() but i get the error 'warning: assignment makes pointer from integer without a cast'. I'd like to store a,b,c e d in a non-pointer array, so I can change them afterwards. How do I convert the from char* to char (afterwards I'll just use atoi() on the strings to get the integers).

Solution

  • To briefly answer your question, the code above should look like this:

    char input[] = "abcd:18:04:12";

char* p1 = strtok(input, ":");
char* p2 = strtok(NULL, ":");
char* p3 = strtok(NULL, ":");
char* p4 = strtok(NULL, ":");

int val1 = atoi(p2);
int val2 = atoi(p3);
int val3 = atoi(p4);

// and now you can do something with val1, val2 and val3

    Note that strtok will place a '\0' character wherever it sees one of your tokens. If you intend to use the input string after, you need a copy of it to pass to strtok.