quoted_translate.c

/* Simple quoted translation program. It reads characters from
 * stdin and writes them to standard out replacing all
 * instances of the character 'WHAT' with the character 'WITH'.
 * If a 'WHAT' character appears between 'QSTART' and 'QEND'
 * (the starting and ending quote characters) it is not
 * replaced. */

#include <stdio.h>
#include <stdbool.h>

#define QSTART '"'
#define QEND '"'
#define WHAT '|'
#define WITH ','

int main() {
    char byte = 0;
    bool quoted = false;
    while (! feof(stdin)) {
        fread(&byte, 1, 1, stdin);
        if ((! quoted) && byte == QSTART) {
            quoted = true;
        } else if (quoted && byte == QEND) {
            quoted = false;
        }
        if ((! quoted) && byte == WHAT) { byte = WITH; }
        fwrite(&byte, 1, 1, stdout);
    }

    return 0;
}