You can open and edit large files, such as logs and exported data, in Textmode. Typing, scrolling, and moving to the next match with Find stay quick in a large document. A few features work differently, as described below.
When you open a file larger than 200 MB, Textmode asks before it opens the file. The alert shows the name and size of the file and the message “Opening such a large file can make the application slow or unresponsive. Do you really want to open the file?”
To open the file, click Open.
To leave it closed, click Cancel.
The larger the file, the longer it takes to open.
Textmode reads the whole file into memory. An open document uses more memory than the size of its file, and more again while the file is opening. Text with characters outside ASCII, such as accented letters or Japanese, needs more memory than plain ASCII text of the same file size.
Find: Find Next shows the next match first, then counts and highlights all matches in the background.
Instances of the selected text: When “Highlight instances of selected text” is on and the document is longer than about 4 million characters, Textmode highlights only the instances near the selection, not those in the whole document.
Syntax highlighting: When a document opens, its beginning is colored first and the rest follows.
Markdown preview: Above 2 MB of text, the preview stops updating as you type. Choose View > Refresh Preview to update it.
Compare With: Each of the two documents can have up to 200,000 lines.
A line longer than 32,768 characters is laid out in pieces of about 16,384 characters, so that typing in it stays quick. The line is shown with an extra break at the start of each piece. The text itself is not changed: no line endings are added to the document.