关于C#：子进程中的程序运行不循环

Program run in child process doesn't loop

我有一个关于从孩子那里阅读stdout的父进程的具体问题。我的问题是，当我运行程序时，子程序应该在循环中多次执行一个新程序，但它只运行一次并退出到父进程。子进程正在运行一个向stdout输出消息的简单程序。
提前致谢。

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#include <sys/types.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <stdlib.h>
#include <signal.h>
#include <unistd.h>
#include
#include <time.h>
#include <sys/wait.h>

#define ssec 1
#define fsec 0
#define secBuf 5
#define decbase 10
#define fgbuf 60




volatile sig_atomic_t aborting = 0;



void chld_handler (int sig)
{
if(sig == SIGINT){


[cc lang="c"] aborting++;

}

}

int rand_start(int low，int high){
int s;
int r = 0;
函数srand(时间(NULL));

s = rand();

r = s％高+低;

返回r;

}

void Usage(){

printf("用法：schedule [-s] [-f] n");
出口(1);

}

int main(int argc，char * argv []){

/ getopt variablen /
int opt;
int index;

int sflag = 0;
int fflag = 0;

char * svalue;
char * fvalue;

int sseconds = ssec;
int fseconds = fsec;

char * reactor;
char * emergency;
char * logfile;

/ ** /
char * endptr;
/管子和儿童/

int pipepc1 [2];
int pipepc2 [2];

int child1_fd;
int child2_fd;

FILE *日志;
FILE * pipe_reader;

char * p;
char * buf;
int waitFc;
int状态;
/ PRGM /
int prg_r;
int prg_e;

/终止/
int cnt = 0;
int start_period;
p = malloc(fgbuf * sizeof(char));
buf = malloc(fgbuf * sizeof(char));

(无效)信号(SIGINT，chld_handler);

if(argc <4){

Usage();

} else if(argc == 4){

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reactor = argv[1];
emergency = argv[2];
logfile = argv[3];

} else if(argc> 4){

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/*argumentenbehandlung*/

while((opt = getopt(argc,argv,":s:f:")) != -1){
printf("sflag %d fflag %d
",sflag,fflag);
printf("opt %c
", opt);
printf("optind %d
",optind);
switch(opt){

case 's':
if(sflag == 0){
sflag++;
svalue = optarg;
}else{
fprintf(stderr,"Widerholung der option -s
");
Usage();
}

break;

case 'f':

if(fflag == 0){

fflag++;
fvalue = optarg;
}else {
fprintf(stderr,"Widerholung der option -f
");
Usage();
}
break;

case ':' :

fprintf(stderr,"Option -%c brauch ein argument
",optopt);
Usage();
break;

case '?' :
fprintf(stderr,"Nicht bekannte option -%c
",optopt);
Usage();
break;

default :
assert(0);

}/*switch*/

}/*while getopt*/

for(index = optind; index < argc; index++){

if((argc - index) == 3){

reactor = argv[index];

}else if((argc - index) == 2){

emergency = argv[index];

}else if((argc - index) == 1){

logfile = argv[index];

}

}/*for schleife*/

/* */
if(sflag){

sseconds = (int)strtol(svalue,&endptr,decbase);
printf("%d ssec
", sseconds);
}

if(fflag){

fseconds = (int)strtol(fvalue,&endptr,decbase);
printf("%d fsec
", fseconds);

}

}

/ pipeing /

if(pipe(pipepc1)== -1){

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fprintf(stderr,"Fehler bei der Erzeugung der pipe
");
exit(1);

} else {printf("Pipe created n");}

/ erzeuge child1 /
child1_fd = fork();

if(child1_fd <0){

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fprintf(stderr,"Fehler beim asfuehren von fork
");
exit(0);

}

if(child1_fd == 0){
的printf("CHILD n");
/关闭管读/
if(close(pipepc1 [0])== -1){

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fprintf(stderr,"Konnte nicht das Read-Ende vom pipepc1 schliessen
");
exit(1);
}

if(close(1) == -1){

fprintf(stderr,"Konnte nicht das Read-Ende vom pipepc1 schliessen
");
exit(1);

}

if(dup(pipepc1[1]) !=STDOUT_FILENO){

fprintf(stderr,"Das setzen des Read-Endes als stdout is Fehlgeschlagen
");
exit(1);

}

if(fseconds == 0){

start_period = sseconds;

}else start_period = rand_start(sseconds,(sseconds + fseconds));

for(cnt = 0; cnt < 5; cnt++){
sleep(start_period);
fflush(stdout);
prg_r = execl(reactor,"",NULL);

//printf("prg_r ist %d
", prg_r);
}

if(close(pipepc1[1]) == -1){

fprintf(stderr,"Das neue stdout konnte nich geschlossen werden
");
exit(1);

}

}其他{

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printf("**PARENT**
");

log = fopen(logfile,"w");

/*schliesse pipe read*/
close(pipepc1[1]);

pipe_reader = fdopen(pipepc1[0],"r");

while((buf = fgets(p,fgbuf,pipe_reader)) != NULL){

printf("from Child : %s
",buf);
fflush(pipe_reader);
}

fclose(log);

waitFc= waitpid(child1_fd,&status,0);

if(waitFc == -1){

fprintf(stderr,"Das Warten ist fehlgeschlagen
");
exit(1);

}

printf("child is done
und waitFc = %d
und satus %d",waitFc,status);
fclose(pipe_reader);
close(pipepc1[1]);

}

printf("argc =％d n"，argc);
出口(0);

}

和反应堆计划：

#include
#include
#include

int main(){

srand(time(NULL));
int i;
int s;

s = rand() % 7;
/*printf("%d
",s);*/

if(s != 6){

printf("OK
");
fflush(stdout);

}else {

printf("PRESSURE TOO HIGH - IMMEDIATE SHUTDOWN REQUIRED");
exit(EXIT_FAILURE);

}