/* */
#include "Process.h" /* */
int main()
{
pid_t pid;
printf("Fork pid:%d
",getpid());
pid = fork();
if(-1 == pid)
{
perror("fork");
exit(1);
}
else if(0 == pid)
{
printf("Child Process!
");
printf("Child Pid:%d
",getpid());
}
else
{
printf("Parent Process!
");
printf("Parent Pid:%d
",getpid());
waitpid(pid,NULL,0); //
}
return 0;
}
/* 1. ，
， ? ? */
/* : waitpid(); , */
/* 2. , .
1 */
/* fork2.c */
/* fork ? */
#include "Process.h" //
int main()
{
pid_t pid;
int count = 0;
pid = fork();
if(-1 == pid) // -1,
{
perror("fork");
exit(1);
}
else if(0 == pid) // 0,
{
count++;
printf("Child count :%d
",count);
}
else // ,
{
count++;
printf("Parent count :%d
",count);
waitpid(pid,NULL,0);
}
return 0;
}
/* : 1. ;
2. " "
3.
*/
/* vfork */
/* 1.vfork ?
2.vfork fork
*/
#include "Process.h"
int main()
{
pid_t pid;
int count = 0;
pid = vfork();
if(-1 == pid)
{
perror("vfork");
exit(1);
}
else if(0 == pid)
{
printf("Child Process!
");
count++;
printf("Child count :%d
",count);
exit(2); //
}
else
{
printf("Parent Process!
");
count++;
printf("Parent count :%d
",count);
}
return 0;
}
/* vfork :
1. ( fork )
2. , ( fork )
3. ( fork )
4. , fork :
*/
/* vfork : */
#include "Process.h"
int main()
{
pid_t pid;
pid = vfork();
if(-1 == pid)
{
perror("vfork");
exit(1);
}
else if(0 == pid)
{
printf("Child Pid:%d
",getpid());
execl("/mnt/hgfs/share/example/Linux/process/fork","./fork",NULL); // ./fork
}
else
{
printf("Parent Process!
");
}
return 0;
}
/* vfork */
/* */
/* waitpid.c */
#include "Process.h"
void ChildRead()
{
int fd,ret;
char buf[20] = {0};
fd = open("hello.txt",O_RDONLY);
if(-1 == fd)
{
perror("open1");
exit(2);
}
ret = read(fd,buf,sizeof(buf));
if(-1 == ret)
{
perror("read");
exit(3);
}
else
{
printf("Read from txt:%s
",buf);
memset(buf,0,sizeof(buf));
}
close(fd);
}
void ParentWrite()
{
int fd;
int ret;
char buf[20] = {0};
fd = open("hello.txt",O_CREAT | O_WRONLY);
if(-1 == fd)
{
perror("open2");
exit(4);
}
printf("Please input the string:
");
scanf("%s",buf);
ret = write(fd,buf,strlen(buf));
if(-1 == ret)
{
perror("write");
exit(5);
}
close(fd);
}
int main()
{
pid_t pid;
pid = fork();
if(-1 == pid)
{
perror("fork");
exit(1);
}
else if(0 == pid)
{
sleep(4);
ChildRead();
}
else
{
ParentWrite();
waitpid(pid,NULL,0);
}
return 0;
}