src/double.c

/* Copyright (c) 1979 Regents of the University of California */
#include <stdio.h>
char    ibuf[BUFSIZ];

main(argc, argv)
        int argc;
        char *argv[];
{
        register char *linp;
        FILE *f;
        register int c;
        char line[1000];

        setbuf(stdout, ibuf);
        argc--;
        argv++;
        f = stdin;
        do {
                if (argc > 0) {
                        close(0);
                        if ((f=fopen(argv[0], "r")) < 0) {
                                perror(argv[0]);
                                exit(1);
                        }
                        argc--, argv++;
                }
                for (;;) {
                        linp = line;
                        for (;;) {
                                c = getc(f);
                                if (c == '\n' || c == -1)
                                        break;
                                *linp++ = c;
                        }
                        if (linp == line) {
                                if (c == '\n')
                                        printf("\n");
                        } else {
                                *linp = 0;
                                printf("%s\r%s\n", line, line);
                        }
                        if (c == -1)
                                break;
                }
        } while (argc > 0);
        fflush(stdout);
        exit(0);
}