~cpp
/**
pipe를 통한 간단한 프로세스 통신의 일예
**/
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>

#define BUFSIZE 30

int main(int argc, char** argv)
{
        int fd[2];
        char buffer[BUFSIZE];
        pid_t pid;
        int state;

        state = pipe(fd);
        if (state == -1) {
                puts("pipe() error");
                exit(1);
        }

        pid = fork();
        if(pid == -1) {
                puts("fork() error");
                exit(1);
        }

        else if (pid == 0) {
                write(fd[1], "Good\n", 6);
        }

        else {
                read(fd[0], buffer, BUFSIZE);
                puts(buffer);
        }

        return 0;
}

gcc pipe1.c -o pipe1 -g

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This GDB was configured as "i486-linux-gnu"...Using host libthread_db library "/lib/tls/libthread_db.so.1".

(gdb) 

(gdb) list
6       #define BUFSIZE 30
7
8       int main(int argc, char** argv)
9       {
10              int fd[2];
11              char buffer[BUFSIZE];
12              pid_t pid;
13              int state;
14
15              state = pipe(fd);
(gdb) 

(gdb) run 15
Starting program: /home/staff/sapius/source/ipc_test/pipe1 15
Good


Program exited normally.
(gdb) list
16              if (state == -1) {
17                      puts("pipe() error");
18                      exit(1);
19              }
20
21              pid = fork();
22              if(pid == -1) {
23                      puts("fork() error");
24                      exit(1);
25              }
(gdb) 

(gdb) break 21
Breakpoint 1 at 0x80484cc: file pipe1.c, line 21.

(gdb) break 21
Breakpoint 1 at 0x80484cc: file pipe1.c, line 21.
(gdb) run
Starting program: /home/staff/sapius/source/ipc_test/pipe1 

Breakpoint 1, main (argc=1, argv=0xbfe98394) at pipe1.c:21
21              pid = fork();
(gdb) print state
$1 = 0
(gdb) print pid
$2 = 0
(gdb) print buffer
$3 = "涌E\203\004\b\001\000\000\000\224\203涌\030\203涌o\205\004\b?217湯?205\004\b"
(gdb) 

(gdb) break 21
Breakpoint 1 at 0x80484cc: file pipe1.c, line 21.
(gdb) run
Starting program: /home/staff/sapius/source/ipc_test/pipe1 

Breakpoint 1, main (argc=1, argv=0xbfda24b4) at pipe1.c:21
21              pid = fork();
(gdb) step 
22              if(pid == -1) {

(gdb) shell gcc pipe3.c -o pipe3 -g
(gdb) exec-file pipe3
(gdb) list
1       #include <stdio.h>
2       #include <unistd.h>
3       //#include <sys/types.h>
4       #include <stdlib.h>
5
6       #define BUFSIZE 30
7
8       int main(int argc, char** argv)
9       {
10              int fd[2];

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