XML Copy editor (like most of the similar programs) try to read in the XML in 1 go. Depending on the formatting of the XML this might take some time. What you are looking for is
byte-stream editor (these load only part of the file before showing you it).
- If it is just browsing a file the command line
less might be interesting.
Less is a program similar to more, but which allows backward movement in the file as well as forward movement. Also, less does not have to read the entire input file before starting, so with large input files it starts up faster than text editors.
- And there is also good old reliable
Sed is a stream editor. A stream editor is used to perform basic text transformations on an input stream (a file or input from a pipeline). While in some ways similar to an editor which permits scripted edits (such as ed), sed works by making only one pass over the input(s), and is consequently more efficient. But it is sed's ability to filter text in a pipeline which particularly distinguishes it from other types of editors.