#include <ctype.h>
#include <stdio.h>
#include <unistd.h>

int main()
{
    char c;

#ifdef STDIO
    FILE *fp_in  = stdin;
    FILE *fp_out = stdout;

    while (fread(&c, 1, 1, fp_in) == 1) {
        c = toupper(c);
        fwrite(&c, 1, 1, fp_out);
    }
#endif

#ifdef UNIX
    int fd_in  = 0;
    int fd_out = 1;

    while (read(fd_in, &c, 1) == 1) {
        c = toupper(c);
        write(fd_out, &c, 1);
    }
#endif
}