simple programming examples for unix v5 cc

unirubik.c for v5

sleep
-----

main(argc, argv)
char **argv;
{
        int c, n;
        char *s;

        n = 0;
        if(argc < 2) {
                printf("arg count\n");
                exit();
        }
        s = argv[1];
        while(c = *s++) {
                if(c<'0' || c>'9') {
                        printf("bad character\n");
                        exit();
                }
                n = n*10 + c - '0';
        }
        sleep(n);
}

adding longs 
------------

main()
{
        int a[2], b[2], c[2];
        char *num;

        a[0] = 1;
        a[1] = 2;
        b[0]=0;
        b[1]=1;
        ladd (c, a, b);
        num = locv (c[0], c[1]);
        printf ("\nThe num is %s", num);

}

create file
-----------

main()
{
        int mf;
        mf = creat ("test001", 0644);
        if (mf < 0)
        {
                printf ("\nFile not created");
        }
        else
        {
                printf ("\nFile created");
        }
        write (mf, "This is a test\n", 15);
        close(mf);
}

double to string
----------------

/* convert double to string */
/* dp is decimal point */
/* sig is sign */

main()
{
        double x;
        char *z;
        int dp, sig;
        x = 1000000.1;

        z = ecvt (x , 8, &dp, &sig);
        printf ("\nNum is %s", z);
        printf ("\nDP is %d", dp);
}

math functions for v5
---------------------

/* examples of math functions for unix v5
   to compile: cc math1.c -lc -la
*/

double sqrt();
double pow();
double gamma();
double exp();

main()
{
        double x,y,z;
        double a,b,c;
        double d1, d2;

        x = 100.00;

        y = sqrt(x);

        printf ("\n%.2f is the square root of %.2f", y,x);
        a = 2.0; b=5.0; c=3.0;
        z = pow (a,b);
        printf ("\n%.2f to the power of %.2f equals %.2f", a,b,z);

        a = gamma (b+1.0);
        a = exp(a);
        printf ("\nfactorial of %.2f is %.2f\n", b, a);
        d1 = 2.0;
        d2 = 5.0;
        a = gamma (d2+1.0) - gamma (d1+1.0) - gamma (d2-d1+1.0);
        a = exp(a);
        printf ("\n%.0f choose %.0f is %.0f\n", d2, d1, a);
}

ceil and floor
--------------

double ceil();
double floor();

main()
{
        double x;

        x = ceil(1000.87);
        printf ("\nCeiling is %f", x);
        x= floor (1000.77);
        printf ("\nFloor is %f", x);
}

multi
-----

#define single 0173030
#define reboot 0173040

main()
{
        if (getcsw() !=single)
        {
                printf ("\nMulti-user mode");
        }
        else
        {
                printf ("\nsingle-user mode");
        }
        printf ("\ngetcsw returns %d", getcsw());
}

reset terminal
--------------

main()
{
        struct tty {
                char ispeed,ospeed;
                char erase,kill;
                int trash;
        } tet;
        gtty(2,&tet);
        tet.erase = 010;
        tet.kill = '\@';
        tet.trash = 0332;
        stty(2,&tet);
        exit(0);
/*

 *
 * Kurt Shoens
 *
 * Very useful after crapping out in raw.
 */
}

inviso
------

#define ECHO 010

struct
{
        int     regs[2];
        int     tflags;
} ttyb;

int sflags;
char str[50];

main()
{
        gtty(0, &ttyb);
        sflags = ttyb.tflags;
        ttyb.tflags =& ~ ECHO;
        stty(0, &ttyb);

        printf ("\nEnter a string: ");

        gets(str);
        printf ("\nYou entered: %s", str);

/* return tty to normal */
        ttyb.tflags = sflags;
        stty(0, &ttyb);
}



get uid
-------

main()
{
        int uid;
        uid = getuid() & 0377;

        printf ("\nUID: %d", uid);
}

get gid
-------

main()
{
        int gid;
        gid = getgid();

        printf ("\nGID: %d", gid);
}

get pid
-------

main()
{
        int pid;
        pid = getpid();

        printf ("\nPID: %d", pid);
}

getpw
-----

main()
{
        int x;
        char buf[80];

        getpw( 4, buf);
        printf ("\nuser is %s", buf);
}

hex to decimal
--------------

main()
{
        int c;
        char buffer[30];

        printf ("\nEnter decimal value: ");
        gets(buffer);
        c = atoi(buffer);
        printf ("\nHex: 0x%x\n", c);
}

cc hex1.c atoi.c gets.c (atoi.c from v6 and gets.c modded from AUSAM)

filter
------

main()
{
    int c;

        while ((c = getchar()) > 0)
        {
          putchar(tolower(c));
        }

    return 0;
}

int tolower(c)
int c;
{
        if(c >= 'A' && c <= 'Z')
                c = c - ('A' - 'a');
        return(c);
}