Various

Environment for writing Michelson contracts

Emacs can be used as a practical environment for writing, editing and debugging Michelson programs. Install it and follow the configuration instructions in the Michelson Emacs README here.

Admin Client

The admin client enables you to interact with the peer-to-peer layer in order to:

  • check the status of the connections

  • force connections to known peers

  • ban/unban peers

A useful command to debug a node that is not syncing is:

tezos-admin-client p2p stat

Tezos binaries: signals and exit codes

Signals: Upon receiving SIGINT (e.g., via Ctrl+C in an interactive session) or SIGTERM (e.g., via systemctl stop) the process will exit (with code 64 or 255, see details below). Note that sending the same signal a second time (after a one (1) second grace period) will terminate the process immediately, interrupting the normal clean-up functions of clean-up (in this case the exit code will be 255).

Exit codes: The meaning of exit codes is presented in the following table. The action column indicates a recommended course of action.

exit code

meaning

action

0

the process exited successfully

nothing

1–125

something went unexpectedly

check output/log to see if you forgot an argument or some such

126

an exception was not handled

report a bug

127

the process received a signal (e.g., via Ctrl-C)

nothing

128

the process was about to exit successfully but an error occurred during exit

check output/logs, clean-up leftover files, open a bug report

129–253

like 1–125 and an error occurred during exit

check output/logs, clean-up leftover files, open a bug report

254

like 126 and an error and an error occurred during exit

check output/logs, clean-up leftover files, open a bug report

255

like 127 but an error and an error occurred during exit (e.g., kill -9)

check output/logs, clean-up leftover files

Failing_noop operation

Starting with protocol 009 a Failing_noop operation is added. This operation is not executable in the protocol and will always fail when injected. It allows to sign an arbitrary string that cannot be misinterpreted in the protocol.

The client has commands to sign a message with a given key or to check that message has been signed by a given key. These commands create a failing_noop operation from the message that is being signed or checked.

tezos-client sign message "hello world" for <account>

tezos-client check that message "hello world" was signed by <account> to
produce <signature>