Thread: Get output to string

Originally Posted by jkepler

I had no luck so far; I've tryed to create a buffer - char buffer[1024] - and append to it the results - strcat(buffer,path) - in the while loop instead of printing - printf("%s", path)...

That wouldn't work, not because the idea is wrong, but because of the implementation details: if you have a char array of 1024 characters, it can at most store a null terminated string of length 1023, but on each iteration of fgets you are reading into a buffer of 1035 characters, i.e., even on the first iteration you could read a string that is too long for your final buffer.

Perhaps you should consider doing dynamic memory allocation, e.g., to realloc on each iteration, or to keep track of the number of chars in use and the number of chars allocated and realloc by a factor when the number of chars in use is about to exceed the number of chars allocated.

By the way, using strcat to append in a loop can be inefficient, i.e., if you always provide a pointer to the start of the array, strcat must search the array for the first null character in order to append, which gets slower and slower as the string gets longer and longer. On the other hand, if you keep track of the string length, you can use strcat to append directly to the end of the string, which would be efficient.