Changes between Version 4 and Version 5 of shunfa/2011/0729

Timestamp:

Jul 29, 2011, 4:02:37 PM (13 years ago)

Author:

shunfa

Comment:

--

shunfa/2011/0729

@@ -92 +92 @@
 
 === 第三階段：修改Source Code ===
+==== Step1. 修改hello.c ====
+{{{
+#!text
+/* hello.c: A program to show the time since the Epoch */
+ 
+#include <stdio.h>
+#include <sys/time.h>
+ 
+int main(int argc, char* argv[])
+{
+   double sec;
+   struct timeval tv;
+ 
+   gettimeofday(&tv, NULL);
+   sec = tv.tv_sec;
+   sec += tv.tv_usec / 1000000.0;
+ 
+   printf("%f\n", sec);
+ 
+   return 0;
+}
+}}}
+
+==== Step2. 更新設定檔 ===
+{{{
+$ autoscan
+$ mv configure.scan configure.ac
+$ autoconf
+$ autoheader
+$ ./configure
+}}}
+
+==== Step3. 修改source code使其支援protable ====
+{{{
+#!text
+/* hello.c: A program to show the time since the Epoch */
+ 
+#include <stdio.h>
+#include "config.h"
+ 
+#ifdef HAVE_SYS_TIME_H
+#include <sys/time.h>
+#else
+#include <time.h>
+#endif
+ 
+double get_sec_since_epoch()
+{
+   double sec;
+ 
+   #ifdef HAVE_GETTIMEOFDAY
+      struct timeval tv;
+ 
+      gettimeofday(&tv, NULL);
+      sec = tv.tv_sec;
+      sec += tv.tv_usec / 1000000.0;
+   #else
+      sec = time(NULL);
+   #endif
+ 
+   return sec;
+}
+ 
+int main(int argc, char* argv[])
+{
+   printf("%f\n", get_sec_since_epoch());
+ 
+   return 0;
+}
+}}}
+
+==== Step4. 編譯及執行 ====
+{{{
+$ autoscan
+$ ./configure
+$ make clean all
+$ ./hello 
+}}}
+