全部博文（489）
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2011-12-22 20:54:18
原文地址：C 管道编程 作者：luozhiyong131
/***************
管道创建与读写
***************/
#include
#include
#include
#include
#include
#define size 256
int main()
{
pid_t pid;
int fd[2];
int status;
char buf[size]="Hello Word\n";
if(pipe(fd)<0)
{
printf("pipe error\n");
exit(0);
}
pid=fork();
if(pid<0)
{
printf("fork error\n");
exit(1);
}
if(pid==0)
{
close(fd[0]);
write(fd[1],buf,sizeof(buf));
}
else
{
close(fd[1]);
read(fd[0],buf,sizeof(buf));
printf("Received message from child process:\n%s",buf);
if(pid!=wait(&status))
{
printf("waite error\n");
exit(1);
}
printf("Done!\n");
}
}
/***************
复制文本文件
***************/
#include
#include
#include
#include
#include
#define size 256
int main(int argc, char **argv)
{
pid_t pid;
FILE *fp;
int fd[2];
int status;
char buf[size];
if(argc!=3)
{
printf("too few arguments\n");
exit(0);
}
if(pipe(fd)<0)
{
printf("pipe error\n");
exit(0);
}
pid=fork();
if(pid<0)
{
printf("fork error\n");
exit(1);
}
if(pid==0)
{
fp=fopen(argv[1],"r");
if(fp==NULL)
{
printf("fopen read error\n");
exit(1);
}
while(fgets(buf,sizeof(buf),fp)!=NULL)
{
close(fd[0]);
write(fd[1],buf,sizeof(buf));
}
fclose(fp);
strcpy(buf,'~');
close(fd[0]);
write(fd[1],buf,sizeof(buf));
}
else
{
fp=fopen(argv[2],"w");
if(fp==NULL)
{
printf("fopen wite error\n");
exit(1);
}
close(fd[1]);
read(fd[0],buf,sizeof(buf));
while('~'!=buf[0]) //?
{
fputs(buf,fp);
close(fd[1]);
read(fd[0],buf,sizeof(buf));
}
fclose(fp);
if(pid!=wait(&status))
{
printf("waite error\n");
exit(1);
}
printf("Done!\n");
}
}
/***************
创建命名管道
***************/
#include
#include
#include
#include
#include
int main(int argc, char **argv)
{
mode_t mode=0750;
int status;
if(argc!=2)
{
printf("too few arguments\n");
exit(0);
}
status=mkfifo(argv[1],mode);
if(status<0)
{
printf("mkfifo erro \n");
exit(0);
}
else
{
printf("fifo create success\n");
}
printf("Done!\n");
return 0;
}
/***************
命名管道之间通信1
***************/
#include
#include
#include
#include
#include
#include
#define size 256
int main(int argc, char **argv)
{
int fd;
int status;
char buf[size];
if(argc!=2)
{
printf("too few arguments\n");
exit(0);
}
status=mkfifo(argv[1],0777);
if(status<0)
{
printf("mkfifo erro \n");
exit(0);
}
fd=open(argv[1],O_RDWR);
if(fd<0)
{
printf("open error");
exit(0);
}
printf("Server\n");
printf("input the massage:");
fgets(buf,sizeof(buf),stdin);
write(fd,buf,sizeof(buf));
printf("send\n");
unlink(argv[1]);
printf("Done!\n");
return 0;
}
/***************
命名管道之间通信2
***************/
#include
#include
#include
#include
#define size 256
int main(int argc, char **argv)
{
int fd;
char buf[size];
if(argc!=2)
{
printf("too few arguments\n");
exit(0);
}
fd=open(argv[1],O_RDONLY);
if(fd<0)
{
printf("open error");
exit(0);
}
printf("Clinet:\n");
read(fd,buf,sizeof(buf));
printf("Received message:%s\n",buf);
printf("Done!\n");
return 0;
}
/**********************
非阻塞方式命名管道之间通信
***********************/
#include
#include
#include
#include
#include
#define size 256
int main(int argc, char **argv)
{
int fd,num;
char buf[size];
if(argc!=2)
{
printf("too few arguments\n");
exit(0);
}
fd=open(argv[1],O_RDWR|O_NONBLOCK);
if(fd<0)
{
printf("open error");
exit(0);
}
while(1)
{
printf("Clinet:\n");
num=read(fd,buf,sizeof(buf));
if(num==-1)
{
if(errno=EAGAIN)
{
printf("No data avlaible\n");
}
}
else
{
printf("read byte:%d\n",num);
printf("Received message:%s\n",buf);
break;
}
sleep(5);
}
printf("Done!\n");
return 0;
}
