strcat() for formatted strings

Question

I\'m building a string piece by piece in my program and am currently using a mix of strcat() when I\'m adding a simple string onto the end, but when im adding a formatted string

Answer 1

Your solution will work. Calling strlen is a bit awkward (particularly if the string gets quite long). sprintf() will return the length you have used [strcat won't], so one thing you can do is something like this:

 char str[MAX_SIZE];
 char *target = str;

 target += sprintf(target, "%s", str_value);
 target += sprintf(target, "somestuff %d", number);
 if (something)
 {
    target += sprintf(target, "%s", str_value2);
 }
 else
 {
    target += sprintf(target, "%08x", num2);
 }

I'm not sure strcat is much more efficient than sprintf() is when used in this way.

Edit: should write smaller examples...