What is the maximum size that an vim or emacs can open & edit?

Question

I would like to know what is the maximum size that an vim or emacs editore can open & edit

Answer 1

The documentation just states this:

Maximum file size 2147483647 bytes (2 Gbyte) when a long integer is 32 bits. Much more for 64 bit longs. Also limited by available disk space for the |swap-file|.

so "much more" will most likely run into your hard drive limitation since it goes to exabytes of alocatable size.

Answer 2

For Emacs the size of a buffer (which a file needs to fit into) is dependent on the max size of an integer (which it uses to stores position locations). This is system dependent. On a 32 bit system, you can hit it. On a 64bit system, in practice, you are unlikely to (i.e. it's terabytes). If you do hit it, then you are likely to have other problems.

There is a package (vlf) which supports editing very large files, which works by virtue of not opening the whole file all at once, with a controllable chunk size.