TLS

Documentation

Websocat4 documentation - it describes some unreleased things too, not only that in 4.0.0-alpha2.
doc.md is a documentation specifically for 4.0.0-alpha2.

Comparing to v4.0.0-alpha1, Websocat4 gained:

--oneshot to serve just one connection
protection from excessively large messages that may overflow memory (it works not the same as in Websocat1 though)
random: endpoint
lengthprefixed: overlay
--inhibit-pongs
--stdout-announce-listening-ports
Ability to inherit socket listeners and other async FDs from parent process, e.g. SystemD
reuse-raw:
readfile:, writefile:, appendfile: (with some additional features for writefile:)
--origin, --ua, -0 helpers

https://github.com/vi/websocat/issues/276 tracks progress of the porting and can sometimes serve as a migration guide.

--exec-dup2 and --exec-dup2-execve to connect sockets (not WebSockets, though) obtained by Websocat4 directly to the process
--random-seed
Additional features for lengthprefixed: mode.
--global-timeout-ms, --sleep-ms-before-start
--exec-after-listen (variation of --stdout-announce-listening-ports)
--compose mode to combine multiple Websocat invocations into one using special arithmetic.
mock_stream_socket: to use Websocat for testing things (or test Websocat itself).
"Registry"-based connections within Websocat (for tests and --compose mode)

Websocat4 documentation - it describes some unreleased things too, not only that in 4.0.0-alpha2.
doc.md is a documentation specifically for 4.0.0-alpha2.

Comparing to v4.0.0-alpha1, Websocat4 gained:

--oneshot to serve just one connection
protection from excessively large messages that may overflow memory (it works not the same as in Websocat1 though)
random: endpoint
lengthprefixed: overlay
--inhibit-pongs
--stdout-announce-listening-ports
Ability to inherit socket listeners and other async FDs from parent process, e.g. SystemD
reuse-raw:
readfile:, writefile:, appendfile: (with some additional features for writefile:)
--origin, --ua, -0 helpers

https://github.com/vi/websocat/issues/276 tracks progress of the porting and can sometimes serve as a migration guide.

--exec-dup2 and --exec-dup2-execve to connect sockets (not WebSockets, though) obtained by Websocat4 directly to the process
--random-seed
Additional features for lengthprefixed: mode.
--global-timeout-ms, --sleep-ms-before-start
--exec-after-listen (variation of --stdout-announce-listening-ports)
--compose mode to combine multiple Websocat invocations into one using special arithmetic.
mock_stream_socket: to use Websocat for testing things (or test Websocat itself).
"Registry"-based connections within Websocat (for tests and --compose mode)