运用fork函数产生的结果不太理解，求解释

=0)&&(strcmp(argv[1],"vfork"!=0)) usage(argv[0]); if((strcmp(argv[1]; } else { a=1; printf(" printf(",char**argv) { int a;/文件名为run #include ),a); exit(0); } } else { printf(" printf("In child process ,chage a to %d\n","：run fork 运行结果： In father process,a=0 you chosed FORK IN child process,chage a to 1 In father process,a=0 you chosed FORK In father process,",a); exit(0); } else { wait(NULL);fork" void usage(char*name) { printf("Usage: %s fork /vfork\n" if(mode==0) { printf("you chosed FORK\fork"))==0) mode=0; else mode=1;n"; #include #include <,a=%d\n"n";n",a); if(fork()==0) { a=1; printf(",a=0 问题;IN child process,chage a to %d \unistd.h> exit(0);n"); } if(vfork()==0) { a=1;,a);,name); exit(1); } int main(int argc,a); exit(0); } } shell运行; int mode; if(argc!=2) usage(argv[0]); if((strcmp(argv[1]; a=0;);In father process;You choosed VFORK\/

1.因为fork会复制父进程的整个内存空间
2.prinf不是实时的输出到屏幕上，而是先输出到缓冲区中
所以fork复制的时候，会把父进程缓冲区中的“you chosed FORK In father process,a=0”也复制进去

要避免这个情况的话，只需要在
if(fork()==0)之前加上一句

fflush(stdout);
把缓冲区清空就可以了

去 再看看别人怎么说的。