我正在尝试做一个我必须使用的家庭作业,fork()但我不知道为什么在通过我的for循环运行它们之后我无法阻止我的叉子:
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/wait.h>
int main(int argc, char *argv[]){
int limit = argc/2;
if(argc%2 == 0){
perror("the number of arguments given must pe even!");
exit(1);
}
int i;
for(i=0; i<=limit; i++){
if(fork()==-1){
perror("childes couldn't be created\n");
exit(1);
}
if(fork()==0){
printf("fork: %d \n",i);
exit(1);
}
wait(0);
}
printf("exiting...\n");
return 0;
}
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输出:
warzaru@ubuntu:~/OS/UprocH$ ./exe a b c d
fork: 0
fork: 0
fork: 1
fork: 1
fork: 1
fork: 2
fork: 2
fork: 1
fork: 2
exiting...
exiting...
fork: 2
exiting...
exiting...
fork: 2
exiting...
exiting...
exiting...
warzaru@ubuntu:~/OS/UprocH$ fork: 2
fork: 2
fork: 2
exiting...
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Daa*_*mer 15
Daniel Fischer强迫我提供答案.
更改:
if(fork()==-1){} // first fork
if(fork()==0){} // second fork
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至:
pid = fork();
if(pid == -1)
{
... //failed
}
else if(pid == 0)
{
... //success
}
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或者使用switch语句:
switch(fork())
{
case -1:
... // failed
break;
case 0:
... // success
break;
}
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