CITS2002 Systems Programming  
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Formatting our results into character arrays

There are many occasions when we wish our "output" to be written to a character array, rather than to the screen.

Fortunately, we need to learn very little - we now call standard function sprintf, rather than printf, to perform our formatting.

#include  <stdio.h>

char chess_outcome[64];

if(winner == WHITE) {
    sprintf(chess_outcome, "WHITE with %i", nwhite_pieces);
}
else {
    sprintf(chess_outcome, "BLACK with %i", nblack_pieces);
}
printf("The winner: %s\n", chess_outcome);

We must be careful, now, not to exceed the maximum length of the array receiving the formatted printing.
Thus, we prefer functions which ensure that not too many characters are copied:

char chess_outcome[64];

//  FORMAT, AT MOST, A KNOWN NUMBER OF CHARACTERS
if(winner == WHITE) {
    snprintf(chess_outcome, 64, "WHITE with %i", nwhite_pieces);
}

//  OR, GREATLY PREFERRED:
if(winner == WHITE) {
    snprintf(chess_outcome, sizeof(chess_outcome), "WHITE with %i", nwhite_pieces);
}

 


CITS2002 Systems Programming, Lecture 6, p9, 9th August 2022.