Do it now!

@echo Hello, World

[CODE] /** * Date : 2005. 11. 14 * * Synopsis : * Parent * | * +--+--+ * | | * Child1 Child2 * * * Child2 -> Chlid1 -> Parent 로 메시지 전달 * */ #include <stdio.h> #include <unistd.h> #include <fcntl.h> int main(void) { int fd[2], fd2[2]; pid_t pid, pid2; char line[255], line2[255]; int n; if ( pipe(fd) < 0 || pipe(fd2) < 0 ) fprintf (stderr, "Error Pid! "); if ( (pid = fork()) < 0 || (pid2 = fork()) < 0 ) fprintf (stderr, "Fork Error "); else if ( pid > 0 ) { close (fd[0]); write (fd[1], "Hello, world! ", 14); } else if ( pid2 > 0) { close (fd[1]); read (fd[0], line2, 14); write (fd2[1], line2, 14); } else { close (fd2[1]); n = read (fd2[0], line, 14); line[n] = '?'; fprintf(stderr, "Chlid : %d %s ", n, line); } return 0; } [/CODE]

[CODE]/* * Prime Number * * Date : 2005. 11. 7 * Made by chobocho@kroea.com * Synopsis : 1 - 1,000,000 까지의 모든 소수를 구하는 프로그램 */ #include <stdio.h> #include <math.h> void process(int end); int main(int argc, char **argv) { process(1000000); getchar(); getchar(); return 0; } void process (int end) { int i, j, temp, flag; int count = 0; if (end >= 2) { //printf ("2 "); count++; } if (end >= 3) { //printf ("3 "); count++; } for (i = 5; i < end; i+=2) { temp = (int)sqrt(i); flag = 0; for (j = 3; j <= temp; j+=2) { if (i % j == 0) { flag = 1; break; } } if ( flag == 0) { // printf ("%d ", i); count++; } } printf ("Total count : %d ", count); }[/CODE]