Geth console use and web3. js use actual combat text has been updated, please go to the original to read

When you’re developing a decentralized ethereum application, you have to interact with Ethereum, and you can’t do that without Web3. The Geth console (REPL) implements all web3 apis and Admin apis, so using Geth well is a required course. Use Geth command to read better.

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Geth console exploration – start and exit

Installation reference Smart contract development environment setup the simplest startup mode is as follows:

$ geth console
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After the GEth console starts successfully, you see the **>** prompt. Exit Enter exit

Geth log control

Redirects logs to files

If you start with the Geth Console, logs will appear from time to time under the current interface. You can output logs to a file in the following ways.

$ geth console 2>>geth.log
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You can open a command line terminal and run the following command to view logs:

$ tail -f geth.log
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Redirect to another terminal

You can also redirect logs to another terminal by typing:

$ tty
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/dev/ttys003 /dev/ttys003

$ geth console 2>> /dev/ttys003
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Start GEth, which is the log output to another terminal. If you do not want to see the log, you can also redirect to an empty terminal:

$ geth console 2>> /dev/null
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Log Level Control

Use **–verbosity** to control log levels. If you do not want to see logs, you can also use:

$ geth --verbosity 0 console
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Start a development mode test node

geth --datadir /home/xxx/testNet --dev console
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Tip: If we often use one way to start, we can save the command as a bash script. ~/bin You can put some common scripts and add ~/bin to the environment variable PATH.

Connect the GETH node

Another way to start GETH is to connect to a GETH node:

$geth attach IPC :/some/custom/path $geth attach http://191.168.1.1:8545 $geth attach ws://191.168.1.1:8546Copy the code

To connect to the development mode node just opened, use:

geth attach ipc:testNet/geth.ipc
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