Appending strings in C

Question

How do I combine multiple strings. For example,

char item[32];
scanf(\"%s\", item);
printf(\"Shopping list: %s\\n\", item); //I want to combine this string          


        

Answer 1

Consider using the great but unknown open_memstream() function.

FILE *open_memstream(char **ptr, size_t *sizeloc);

Example of usage :

// open the stream
FILE *stream;
char *buf;
size_t len;
stream = open_memstream(&buf, &len);

// write what you want with fprintf()
char item[32];
scanf("%s", item);
fprintf(stream, "Shopping list: %s\n", item);
char string_2[] = "To do list: Sleep\n";
fprintf(stream, "%s\n", string_2);
char hw[32];
scanf("%s", hw); 
fprintf(stream, "Homework: %s\n", hw);

// close the stream, the buffer is allocated and the size is set !
fclose(stream);
printf ("the result is '%s' (%d characters)\n", buf, len);
free(buf);

Let the kernel manage the buffer allocation, it does it better than you !