Null keepalive char from terminal causes "Directory Scanning"

[bw.aljex@…]

I have a terminal emulator configured to send an ascii null every few seconds. This is invisible to most programs, but keeps tcp sessions alive in aggressive routers.

In MC, every time the null gets sent by the terminal emulator, mc pops up a Directory Scanning popup, which gets in the way of actually using mc since I happen to have had the setting sending them very frequently.

mc 4.8.12 on OSX (from ​http://www.midnight-commander.org/wiki/Binaries)

(Copied over from ​https://github.com/MidnightCommander/mc/issues/87)

[and]

On TCP level you have tcp keepalive, ok let assume aggressive router don't respect tcp keepalive.

On data payload level let guess using ssh you have ServerAliveInterval? for sending 0 Byte from client to server. TCP data payload will be around 20-30Bytes depends on ssh encryption.
even aggressive router will see normal tcp traffic equal with your NUL terminal insertion.

It is unusual to insert NUL string on terminal level, maybe bad things happen. :)

Anyway what menu do you mean with Directory Scanning in mc?

[zaytsev]

Hi Brian, could you please clarify?

[mooffie]

NULL is C-space (do cat | od -c, and hit C-space (or C-@) and ENTER and C-d to see), which is the "Show directory sizes" command.

If this is your case, there isn't a bug here. (Tip: google ServerAliveInterval.)