如何检查文件名和变量名是否相同

Question

实际上，问题是，系统升级时，应在根目录中写入“ DISABLE_BACKUP”文件。当它出现时，我必须检查文件是否已经在根目录中。

    if ((dir = opendir ("/"))!=NULL)
    {
        while ((ent = readdir(dir)) != NULL)
        {
            printf ("%s\n", ent->d_name);

        //Here i have to compare the filename (DISABLE_BACKUP) with the string "DISABLE_BACKUP" and has to raise log entry.
        }
    closedir(dir);
    }

Answer 1

1. 比较字符串的C函数为strcmp()：

   if (strcmp(ent->d_name, "DISABLE_BACKUP")==0) {
      // Found it!
   

2. 也许更好的方法来查看文件“ DISABLE_BACKUP”是否存在为access()：

   #include <unistd.h>
   ...
   if (access(fname, F_OK) != -1) {
      // file exists
   } else {
      // file doesn't exist
   }