1

fock/.vscode/settings.json

@@ -0,0 +1,5 @@
+{
+    "files.associations": {
+        "unistd.h": "c"
+    }
+}

fock/fock.c

@@ -1,5 +1,53 @@
 #include <stdio.h>
-int main(void){
+#include <sys/types.h>
-    printf("hello\n");
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <sys/wait.h>
+#include <sys/stat.h>
+#include <signal.h>
+
+extern char **environ;
+
+
+int weak_process(){
+    printf("get signal\n");
+}
+int main(void)
+{
+    // 获取进程ID
+    printf("I am %d \n", getpid());
+    printf("My parent is %d\n", getppid());
+    // 打印环境变量
+    // char **env = environ;
+    // while (*env != NULL)
+    // {
+    //     printf("%s\n", *env);
+    //     *env++;
+    // }
+    // fock创建进程
+    // fock创建的子进程一般用来执行新的程序
+    signal(SIGUSR1,weak_process);
+    pid_t pid = fork();
+    if (pid == 0)
+    {
+        printf("I am child process %d\n", getpid());
+        sleep(10);
+        _exit(0);
+    }
+    else if (pid > 0)
+    {
+        sleep(1);
+        kill(pid,SIGUSR1);
+        wait(NULL);
+        // printf("pit = %d\n",pid);
+        printf("I am parent process %d\n", getpid());
+    }
+    else
+    {
+        printf("fork error\n");
+    }
+    
     return 0;
 }