*** test.txt 文件必须存在 ***
store fopen('test.txt') to gnfilehandle && 打开文件
store fseek(gnfilehandle, 0, 2) to gnend && 移动指针到 eof
store fseek(gnfilehandle, 0) to gntop && 移动指针到bof
if gnend <= 0 && 是“空”文件吗?
wait window 'this file is empty!' nowait
else && 如果非“空”
gcstring = fgets(gnfilehandle, gnend) && 存储内容
? gcstring
endif
= fclose(gnfilehandle) && 关闭文件