string - concatenate char array in C

Question

I have a a char array:

char* name = "hello";

I want to add an extension to that name to make it

hello.txt

How can I do this?

name += ".txt" won't work

Answer 1

Have a look at the strcat function.

In particular, you could try this:

const char* name = "hello";
const char* extension = ".txt";

char* name_with_extension;
name_with_extension = malloc(strlen(name)+1+4); /* make space for the new string (should check the return value ...) */
strcpy(name_with_extension, name); /* copy name into the new var */
strcat(name_with_extension, extension); /* add the extension */