test

exp1/.vscode/launch.json

@@ -0,0 +1,7 @@
+{
+    // 使用 IntelliSense 了解相关属性。 
+    // 悬停以查看现有属性的描述。
+    // 欲了解更多信息，请访问: https://go.microsoft.com/fwlink/?linkid=830387
+    "version": "0.2.0",
+    "configurations": []
+}

exp1/.vscode/tasks.json

@@ -0,0 +1,28 @@
+{
+    "tasks": [
+        {
+            "type": "cppbuild",
+            "label": "C/C++: gcc 生成活动文件",
+            "command": "/usr/bin/gcc",
+            "args": [
+                "-fdiagnostics-color=always",
+                "-g",
+                "${file}",
+                "-o",
+                "${fileDirname}/${fileBasenameNoExtension}"
+            ],
+            "options": {
+                "cwd": "${fileDirname}"
+            },
+            "problemMatcher": [
+                "$gcc"
+            ],
+            "group": {
+                "kind": "build",
+                "isDefault": true
+            },
+            "detail": "调试器生成的任务。"
+        }
+    ],
+    "version": "2.0.0"
+}

exp1/badcount.c

@@ -0,0 +1,62 @@
+#include <pthread.h>
+#include <time.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+int cnt = 0;
+sem_t mutex;
+
+void *increase(void *vargp)
+{
+    unsigned int niters = (unsigned int)vargp;
+    for (unsigned int i = 0; i < niters; i++)
+    {
+        sem_wait(&mutex);
+        cnt++;
+        sem_post(&mutex);
+    }
+    return NULL;
+}
+
+void *decrease(void *vargp)
+{
+    unsigned int niters = (unsigned int)vargp;
+    for (unsigned int i = 0; i < niters; i++)
+    {
+        sem_wait(&mutex);
+        cnt--;
+        sem_post(&mutex);
+    }
+    return NULL;
+}
+
+int main(int argc, char **argv)
+{
+    unsigned int niters;
+    pthread_t t1,t2;
+
+    if (argc != 2)
+    {
+        printf("Usage: %s <niters>\n", argv[0]);
+        exit(2);
+    }
+    niters = atoll(argv[1]);
+
+    sem_init(&mutex, 0, 1);
+    pthread_create(&t1,NULL,increase,(void*)niters);
+    pthread_create(&t2,NULL,decrease,(void*)niters);
+    pthread_join(t1,NULL);
+    pthread_join(t2,NULL);
+
+    if (cnt != 0)
+    {
+        printf("Error! cnt=%d\n", cnt);
+    }
+    else
+    {
+        printf("Correct! cnt=%d\n", cnt);
+    }
+    sem_destroy(&mutex);
+    exit(0);
+}

exp1/task61.c

@@ -0,0 +1,53 @@
+#include <pthread.h>
+#include <time.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+void *wokerT1(void *vargp)
+{
+    for(int i=0; i<5; i++)
+    {
+        printf("My name is Lvjinzhong\n");
+        int sleep_time = rand() % 5 + 1;
+        sleep(sleep_time);
+    }
+    return NULL;
+}
+
+void *wokerT2(void *vargp)
+{
+    for(int i=0; i<5; i++)
+    {
+        printf("My student number is 2024414290124\n");
+        int sleep_time = rand() % 5 + 1;
+        sleep(sleep_time);
+    }
+    return NULL;
+}
+
+void *wokerT3(void *vargp)
+{
+    for(int i=0; i<5; i++)
+    {
+        time_t t = time(NULL);
+        printf("Current time %s\n",ctime(&t));
+        int sleep_time = rand() % 5 + 1;
+        sleep(sleep_time);
+    }
+    return NULL;
+}
+
+int main()
+{
+    pthread_t t1,t2,t3;
+    pthread_create(&t1, NULL, wokerT1, NULL);
+    pthread_create(&t2, NULL, wokerT2, NULL);
+    pthread_create(&t3, NULL, wokerT3, NULL);
+    
+    
+    pthread_join(t1, NULL);
+    pthread_join(t2, NULL);
+    pthread_join(t3, NULL);
+    return 0;
+}