gedit如何在文件加载完成之前编辑并保存大文件？

I wanted to edit just the first line of a 4 MB file. When I open files this large in gedit, it takes a minute or two to load the file but displays and allows you to edit the part that it has loaded so far. So I opened the file, quickly edited the first line, saved the file, and closed gedit all before it was even close to finishing loading the file.I wanted to edit just the first line of a 4 MB