第二章完结

Chapter1/基本概念-编程注意问题/a.c

@@ -0,0 +1,18 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <string.h>
+
+int main()
+{
+    FILE *fp;
+
+    fp = fopen("tmp", "r");
+    if (fp == NULL)
+    {
+        fprintf(stderr, "fopen():%s\n", strerror(errno));
+        exit(1);
+    }
+    puts("ok!");
+    exit(0);
+}

Chapter1/基本概念-编程注意问题/hello.c

@@ -0,0 +1,12 @@
+#include <stdio.h>
+
+int main(void)
+{
+    int *p = NULL;
+    int i;
+    p = (int *)malloc(sizeof(int));
+    if (p == NULL)
+        return -1;
+    printf("Hello world!\n");
+    return 0;
+}

Chapter1/基本概念-编程注意问题/return.c

@@ -0,0 +1,6 @@
+#include <stdio.h>
+
+int main(void)
+{
+    printf("Hello world!\n");
+}