그것은 c의 리눅스 쉘의 구현입니다. 백그라운드 프로세스 지원을 추가했기 때문에 이해가 안되는 출력이 있습니다. 여기에 코드입니다 : 내가 "LS &"같은 BG 명령을 실행하면내 프로세스가 이와 같이 작동합니까?
#include <stdlib.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <signal.h>
#include <wait.h>
#define DEFAULT_PROMPT "\nLog710H2014%>"
#define EXIT_CMD "exit"
#define CD_CMD "cd"
#define HOME_ENV_VAR "HOME"
#define NEW_LINE "\n**************************************************\n"
#define BCG_CMD_FLAG "&"
void cd_handler(int argc, char *argv[]);
int lire(char *chaine, int longueur);
char** init_command(int* size,char *str);
int execProg(int *argc, char **argv);
int execProgBg(int *argc, char **argv);
void sigchldHandler(int sig_num);
struct beanProcess {
pid_t pid;
int job_num;
char *command;
};
struct beanProcess *beans;
int jobCount = 1;
int main() {
printf(NEW_LINE);
printf("Bienvenue sur le shell de l'equipe 1");
printf(NEW_LINE);
while(1){
char str[200];
printf(DEFAULT_PROMPT);
lire(str, 200);
int commArgsC = 0, bg = 0;
char** comms = init_command(&commArgsC, str);
if(commArgsC == 0){
printf("Saisie vide, veuillez entrez une commande.");
continue;
}
if(strcmp(comms[commArgsC-1], BCG_CMD_FLAG) == 0){
bg = 1;
comms[commArgsC-1] = 0;
}
if(strcmp(comms[0], CD_CMD) == 0){
cd_handler(commArgsC, comms);
commArgsC = commArgsC -1;
}
else if (strcmp(comms[0], EXIT_CMD) == 0){
exit(0);
}
else {
if(bg){
execProgBg(&commArgsC, comms);
}
else{
execProg(&commArgsC, comms);
}
}
}
exit;
}
void cd_handler(int argc, char *argv[]){
char buff[512];
char * directory;
if(argc < 2){
directory = getenv(HOME_ENV_VAR);
}else if (argc == 2){
directory = argv[1];
}else{
exit(1);
}
if (chdir(directory) == -1) {
printf ("Erreur de changement de repertoire actif", strerror (errno));
}else{
if (getcwd(buff, sizeof(buff)) == NULL)
perror("Impossible d'afficher le repertoire courant");
else
printf("le repertoire courant est: %s\n", buff);
}
}
//Cette fonction est adaptée a partir du code de refp sur http://stackoverflow.com/questions/11198604/c-split-string-into-an-array-of-strings
char** init_command(int* size, char* str){
char ** res = NULL;
char * p = strtok (str, " ");
int n_spaces = 0;
while (p) {
res = realloc (res, sizeof (char*) * ++n_spaces);
if (res == NULL){
exit (-1);
}
res[n_spaces-1] = p;
p = strtok (NULL, " ");
}
res = realloc (res, sizeof (char*) * (n_spaces+1));
res[n_spaces] = 0;
*size = n_spaces;
return res;
}
//cette fonction est tirée d'un exemple de http://fr.openclassrooms.com/informatique/cours/apprenez-a-programmer-en-c/recuperer-une-chaine-de-caracteres
int lire(char *chaine, int longueur)
{
char *positionEntree = NULL;
if (fgets(chaine, longueur, stdin) != NULL)
{
positionEntree = strchr(chaine, '\n');
if (positionEntree != NULL)
{
*positionEntree = '\0';
}
return 1;
}
else
{
return 0;
}
}
int execProg(int *argc, char **argv){
char path[] = "/bin/";
strcat(path,argv[0]);
printf("\nThis is the %d process executing the code in non bg mode\n", getpid());
printf("Voici le resultat de l'execution de votre commande\n");
pid_t pid;
pid = fork();
if (pid < 0) {
perror("Creation de processus avec fork echouee");
exit(-1);
}
else if (pid == 0) {
if(execvp(argv[0], argv) == -1){
printf("\nthis is the child process %d executing the command in non bg mode\n", getpid());
perror("execv");
return EXIT_FAILURE;
}
}
else {
printf("\nthis is the parent process %d showing the stats in non bg mode\n", getpid());
struct rusage rusg;
long temp, tempCpu;
wait (NULL);
getrusage(RUSAGE_CHILDREN, &rusg);
printf("\nStatistique de la commande %s:\n", argv[0]);
temp = (rusg.ru_utime.tv_sec * 1000) + (rusg.ru_utime.tv_usec/1000);
tempCpu = (rusg.ru_stime.tv_sec * 1000) + (rusg.ru_stime.tv_usec/1000);
printf("\nLe temps wall-clock (ms): %ld", temp);
printf("\nLe temps CPU (ms) %ld", tempCpu);
printf("\nNB interruptions volontaires: %ld", rusg.ru_nvcsw);
printf("\nNB interruptions involontaires: %ld", rusg.ru_nivcsw);
printf("\nNB defaults de pages: %ld", rusg.ru_majflt);
printf("\nNB defaults de pages satifaits du noyau : %ld", rusg.ru_minflt);
}
return EXIT_SUCCESS;
}
int execProgBg(int *argc, char **argv){
signal(SIGCHLD, sigchldHandler);
printf("\nThis is the %d process executing the code in bg mode\n", getpid());
pid_t pid;
pid = fork();
if (pid < 0) {
perror("Creation de processus avec fork echouee");
return EXIT_FAILURE;
}
else if (pid == 0) {
//printf("This is the pid %d", getpid());
printf("\nthis is the child process %d executing the command in bg mode\n", getpid());
if(execvp(argv[0], argv) == -1){
perror("execvp");
return EXIT_FAILURE;
}
}
else {
printf("\nthis is the parent process %d showing the queue in bg mode\n", getpid());
printf("[%d] %d", jobCount, pid);
jobCount++;
//cleanJobList(childPid);
//ajoutProcess();
}
return EXIT_SUCCESS;
}
void sigchldHandler(int sig_num)
{
int status;
int childPid;
childPid = waitpid(-1, &status, 1);
printf("Hello the process %d has died\n", childPid);
//cleanJobList(childPid);
}
, 여기에 출력입니다 :
**************************************************
Bienvenue sur le shell de l'equipe 1
**************************************************
Log710H2014%>ls &
This is the 23464 process executing the code in bg mode
this is the parent process 23464 showing the queue in bg mode
[1] 23472
Log710H2014%>
this is the child process 23472 executing the command in bg mode
Debug PARTIE3.c
Hello the process 23472 has died
This is the 23464 process executing the code in non bg mode
Voici le resultat de l'execution de votre commande
this is the parent process 23464 showing the stats in non bg mode
Debug PARTIE3.c
Statistique de la commande ls:
Le temps wall-clock (ms): 0
Le temps CPU (ms) 2
NB interruptions volontaires: 2
NB interruptions involontaires: 9
NB defaults de pages: 0
NB defaults de pages satifaits du noyau : 644
Log710H2014%>
왜 부모 프로세스가 리라() 함수를 중첩되어 있고 직접 이동 첫 번째 실행 후 execProg 함수에?
'디버그 PARTIE3.c '는 어디에서 왔습니까? – Nabla
명령 ls & – user2966439