对于两个程序之间的进行交互式
本程序主要通过父进程创建两个子进程，通过管道来实现，和两人无序对话的功能一样。只要逻辑清晰，并不难。共需要pipe（有名管道）六根，功能为用于读、写，为了使逻辑清晰，方便讨论，以下1、2、3分别代表程序1、2、3之间的管道，分别对程序之间的管道进项讨论分析：
| A | B | C | |||
| 1-2 | write | 1-2 | read | 1-3 | read |
| 1-3 | write | 2-1 | write | 3-1 | write |
| 2-1 | read | 2-3 | write | 2-3 | read |
| 3-1 | read | 3-2 | read | 3-2 | write |
以上表格表示的具体含义我在这里举例说明一下。eg：对于A（聊天猪头）而言共有四根管道与其相连，两根用于读，另外两根用于写，1-2管道代表A、B之间的管道A需要进行写操作，而B进行读操作。
- A:第一人
1 /*============================================
2 > Copyright (C) 2014 All rights reserved.
3 > FileName：1.c
4 > author：donald
5 > date：2014/08/22/ 20:28:53
6 > details：
7 ==============================================*/
8
9 #include <stdio.h>
10 #include <stdlib.h>
11 #include <string.h>
12 #include <sys/types.h>
13 #include <sys/stat.h>
14 #include <fcntl.h>
15 #define N 1024
16 int main(int argc, const char *argv[])//12,13,21,31
17 {
18 if(mkfifo(argv[1],0666) == -1 || mkfifo(argv[2],0666) == -1){
19 perror("mkfifo");
20 exit(1);
21 }
22
23 int fd_12,fd_13,fd_21,fd_31;
24 char buf[N];
25 fd_12 = open(argv[1],O_WRONLY);
26 fd_13 = open(argv[2],O_WRONLY);
27 fd_21 = open(argv[3],O_RDONLY);
28 fd_31 = open(argv[4],O_RDONLY);
29
30 printf("open sucess\n");
31
32 if(fork() == 0){//21 r
33 close(fd_13);
34 close(fd_12);
35 close(fd_31);
36 while(memset(buf,0,N),read(fd_21,buf,N) != 0){
37 printf("from 2:");
38 write(1,buf,strlen(buf));
39 }
40 close(fd_21);
41 exit(1);
42 }
43 if(fork() == 0){//31 r
44 close(fd_13);
45 close(fd_12);
46 close(fd_21);
47 while(memset(buf,0,N),read(fd_31,buf,N) != 0){
48 printf("from 3:");
49 write(1,buf,strlen(buf));
50 }
51 close(fd_31);
52 exit(1);
53 }
54
55 //12 13 w
56 close(fd_21);
57 close(fd_31);
58 while(memset(buf,0,N),fgets(buf,N,stdin) != NULL){
59 write(fd_13,buf,strlen(buf));
60 write(fd_12,buf,strlen(buf));
61 }
62 close(fd_13);
63 close(fd_12);
64 wait(NULL);
65 wait(NULL);
66
67 unlink(argv[1]);
68 unlink(argv[2]);
69 printf("program 1 over\n");
70 return 0;
71 }
1.c
- B:第二人
1 /*============================================
2 > Copyright (C) 2014 All rights reserved.
3 > FileName：2.c
4 > author：donald
5 > date：2014/08/22/ 20:29:02
6 > details：
7 ==============================================*/
8
9 #include <stdio.h>
10 #include <stdlib.h>
11 #include <string.h>
12 #include <sys/types.h>
13 #include <sys/stat.h>
14 #include <fcntl.h>
15 #define N 1024
16 int main(int argc, const char *argv[])
17 {
18
19 if(mkfifo(argv[2],0666) == -1 || mkfifo(argv[3],0666) == -1){
20 perror("mkfifo");
21 exit(1);
22 }
23
24 int fd_12,fd_21,fd_23,fd_32;
25 char buf[N];
26 fd_12 = open(argv[1],O_RDONLY);
27 fd_21 = open(argv[2],O_WRONLY);
28 fd_23 = open(argv[3],O_WRONLY);
29 fd_32 = open(argv[4],O_RDONLY);
30
31 printf("open success\n");
32
33 if(fork() == 0){//12 r
34 close(fd_32);
35 close(fd_21);
36 close(fd_23);
37 while(memset(buf,0,N),read(fd_12,buf,N) != 0){
38 printf("from 1:");
39 write(1,buf,strlen(buf));
40 }
41 close(fd_12);
42 exit(1);
43 }
44
45 if(fork() == 0){//32 r
46 close(fd_12);
47 close(fd_21);
48 close(fd_23);
49 while(memset(buf,0,N),read(fd_32,buf,N) != 0){
50 printf("from 3:");
51 write(1,buf,strlen(buf));
52 }
53 close(fd_32);
54 exit(1);
55 }
56
57 //21 23 w
58 close(fd_12);
59 close(fd_32);
60 while(memset(buf,0,N),fgets(buf,N,stdin) != NULL){
61 write(fd_21,buf,strlen(buf));
62 write(fd_23,buf,strlen(buf));
63 }
64 close(fd_21);
65 close(fd_23);
66 wait(NULL);
67 wait(NULL);
68
69 unlink(argv[2]);
70 unlink(argv[3]);
71 printf("program 2 over\n");
72 return 0;
73 }
2.c
- C:第三人
1 /*============================================
2 > Copyright (C) 2014 All rights reserved.
3 > FileName：3.c
4 > author：donald
5 > date：2014/08/22/ 20:29:13
6 > details：
7 ==============================================*/
8 #include <stdio.h>
9 #include <stdlib.h>
10 #include <string.h>
11 #include <sys/types.h>
12 #include <sys/stat.h>
13 #include <fcntl.h>
14 #define N 1024
15 int main(int argc, const char *argv[])
16 {
17
18 if(mkfifo(argv[2],0666) == -1 || mkfifo(argv[4],0666) == -1){
19 perror("mkfifo");
20 exit(1);
21 }
22
23 int fd_13,fd_31,fd_23,fd_32;
24 char buf[N];
25 fd_13 = open(argv[1],O_RDONLY);
26 fd_31 = open(argv[2],O_WRONLY);
27 fd_23 = open(argv[3],O_RDONLY);
28 fd_32 = open(argv[4],O_WRONLY);
29
30 printf("open success\n");
31
32 if(fork() == 0){//13 r
33 close(fd_31);
34 close(fd_23);
35 close(fd_32);
36 while(memset(buf,0,N),read(fd_13,buf,N) != 0){
37 printf("from 1:");
38 write(1,buf,strlen(buf));
39 }
40 close(fd_13);
41 exit(1);
42 }
43 if(fork() == 0){//23 r
44 close(fd_13);
45 close(fd_31);
46 close(fd_32);
47 while(memset(buf,0,N),read(fd_23,buf,N) != 0){
48 printf("from 2:");
49 write(1,buf,strlen(buf));
50 }
51 close(fd_23);
52 exit(1);
53 }
54
55 //31 32 w
56 close(fd_13);
57 close(fd_23);
58 while(memset(buf,0,N),fgets(buf,N,stdin) != NULL){
59 write(fd_31,buf,strlen(buf));
60 write(fd_32,buf,strlen(buf));
61 }
62 close(fd_31);
63 close(fd_32);
64 wait(NULL);
65 wait(NULL);
66
67 unlink(argv[2]);
68 unlink(argv[4]);
69 printf("program 3 over\n");
70 return 0;
71 }
3.c
PS:在命令行参数中还需注意的，假设1.c、2.c、3.c的可执行文件为A.out、B.out、C.out。命令行参数分别为：(其实和表格里分析的一样)
-
-
-
-
-
- ./A.out 12.fifo 13.fifo 21.fifo 31.fifo
- ./B.out 12.fifo 21.fifo 23.fifo 32.fifo
- ./C.out 13.fifo 31.fifo 23.fifo 32.fifo
-
-
-
-
时间： 2024-11-03 22:07:39