LR函数研究fopen
首先，可以从LR函数帮助中查找到fopen函数定义如下，返回值是FILE *类型。FILE *fopen ( const char *filename, const char *access_mode );我们再看看它给出的例子程序，发现将其返回值赋给长整形变量file_stream;
file_stream = fopen(filename, "r")== NULL ;
这里我不能理解，怎么不是赋给一个文件指针类型变量？望高手们回答……
Action() {
int count, total = 0;
char buffer;
long file_stream;
char *filename = "c:\\readme.txt";
/* Open the file with read access */
if ((file_stream = fopen(filename, "r")) == NULL ) {
lr_error_message("Cannot open %s", filename);
return -1;
}
/* Read until end of file */
while (!feof(file_stream)) {
/* Read 1000 bytes while maintaining a running count */
count = fread(buffer, sizeof(char), 1000, file_stream);
lr_output_message("%3d read", count);
/* Check for file I/O errors */
if (ferror(file_stream)) {
lr_output_message("Error reading file %s", filename);
break;
}
total += count; /* add up actual bytes read */
}
/* Display final total */
lr_output_message("Total number of bytes read = %d", total );
/* Close the file stream */
if (fclose(file_stream))
lr_error_message("Error closing file %s", filename);
return 0;
} 这里是返回操作状态码的，如果返回是真，则继续，否则取消 请问，指针和long，有啥区别呢？
都是变量，一样的用~~
貌似C的fopen就是这样的返回值
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