为什么我的Perl脚本会从文件中删除字符？

I have some issue with a Perl script. It modifies the content of a file, then reopen it to write it, and in the process some characters are lost. All words starting with '%' are deleted from the file. That's pretty annoying because the the % expressions are variable placeholders for dialog boxes.I have some issue with a Perl script. It modifi