The c_cc field of struct termios is an array of bytes. Each byte holds the ASCII value of one special character. You index into the array using the V-prefixed constants (VEOF, VINTR, VERASE, etc.).

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

int main(void) {
    struct termios tp;

    if (tcgetattr(STDIN_FILENO, &tp) == -1) {
        perror("tcgetattr");
        return 1;
    }

    /* Print the current special character values */
    printf("EOF character  : ^%c (ASCII %d)\n",
           tp.c_cc[VEOF] + '@', tp.c_cc[VEOF]);
    printf("INTR character : ^%c (ASCII %d)\n",
           tp.c_cc[VINTR] + '@', tp.c_cc[VINTR]);
    printf("ERASE character: ^%c (ASCII %d)\n",
           tp.c_cc[VERASE] - 1 + 'A', tp.c_cc[VERASE]);
    printf("KILL character : ^%c (ASCII %d)\n",
           tp.c_cc[VKILL] + '@', tp.c_cc[VKILL]);
    printf("SUSP character : ^%c (ASCII %d)\n",
           tp.c_cc[VSUSP] + '@', tp.c_cc[VSUSP]);

    return 0;
}

This covers all characters recognized by the Linux terminal driver.

Three special characters send signals to the foreground process group. They are controlled by the ISIG flag. If ISIG is cleared in c_lflag, these characters no longer generate signals — they are passed to the reading process as data.

#include <termios.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>

/* Disable signal generation from INTR, QUIT, SUSP keys */
int main(void) {
    struct termios tp;

    if (tcgetattr(STDIN_FILENO, &tp) == -1) {
        perror("tcgetattr");
        return 1;
    }

    /* Clear ISIG flag — ^C, ^\, ^Z now pass as raw bytes instead of signals */
    tp.c_lflag &= ~ISIG;

    if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &tp) == -1) {
        perror("tcsetattr");
        return 1;
    }

    printf("Signals disabled. ^C is now just a byte.\n");
    printf("Press ^C (won't kill): ");
    fflush(stdout);

    int ch = getchar();
    printf("Got character with ASCII value: %d\n", ch);

    /* Restore */
    tp.c_lflag |= ISIG;
    tcsetattr(STDIN_FILENO, TCSAFLUSH, &tp);

    return 0;
}

You can disable any special character by setting its c_cc slot to the value returned by:

fpathconf(fd, _PC_VDISABLE)

On most Linux/UNIX systems, this returns 0. Setting a c_cc slot to 0 (or more precisely to _POSIX_VDISABLE) means that character is completely disabled — pressing the corresponding key has no special meaning at all; it passes through to the reading process as raw data.

#include <termios.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>

int main(void) {
    struct termios tp;
    long vdisable;

    /* Get the disable value for this terminal */
    vdisable = fpathconf(STDIN_FILENO, _PC_VDISABLE);
    if (vdisable == -1) {
        perror("fpathconf");
        return 1;
    }
    printf("VDISABLE value: %ld\n", vdisable);

    if (tcgetattr(STDIN_FILENO, &tp) == -1) {
        perror("tcgetattr");
        return 1;
    }

    /* Disable the EOF character (^D will no longer mean EOF) */
    tp.c_cc[VEOF] = (cc_t) vdisable;

    /* Disable the INTR character (^C won't send SIGINT) */
    tp.c_cc[VINTR] = (cc_t) vdisable;

    if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &tp) == -1) {
        perror("tcsetattr");
        return 1;
    }

    printf("EOF and INTR characters disabled.\n");

    /* Don't forget to restore before exit! */
    /* ... restore code ... */

    return 0;
}

You can reassign any special character to a different key by writing a new value into c_cc:

#include <termios.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>

int main(void) {
    struct termios tp;

    if (tcgetattr(STDIN_FILENO, &tp) == -1) {
        perror("tcgetattr");
        return 1;
    }

    /* Change EOF from ^D (ASCII 4) to ^E (ASCII 5) */
    tp.c_cc[VEOF] = 5;  /* Ctrl+E = ASCII 5 */

    /* Change INTR from ^C (ASCII 3) to ^L (ASCII 12) */
    tp.c_cc[VINTR] = 12; /* Ctrl+L = ASCII 12 */

    if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &tp) == -1) {
        perror("tcsetattr");
        return 1;
    }

    printf("EOF is now ^E, INTR is now ^L\n");

    /* ... restore before exit ... */

    return 0;
}

The table shows that CR (carriage return, ^M) and NL (newline, ^J) do NOT have c_cc subscripts. This is because their values are fixed by the ASCII standard and cannot be changed.

However, their behavior can still be controlled through flags:

Two special slots in c_cc, VMIN and VTIME, are not character values. Instead, they control how reads behave in noncanonical mode.

In the stty -a output you saw: min = 1; time = 0;

These are covered in detail in the noncanonical mode section (Chapter 62.6.2). The key point here is that they live in c_cc but serve a completely different purpose from the other entries.