What does echo mean?

What does echo mean?

ECHO is a computer command.

It can be based on the TCP protocol. The server detects whether there is a message on TCP port 7. If the UDP protocol is used, the basic process is the same as TCP, and the detected port is also 7. Routing is also the most commonly used data packet in the network. You can know which paths the current connection node has by sending echo packets, and the path length can be obtained through the round-trip time.

Echo contains three versions:

1. Echo1 uses a hidden Iframe to achieve the effect of asynchronous communication, and its performance is relatively low.

2. Echo2 is the next generation version of the Echo Web framework. A framework that can be used to develop web-based thick client applications. This version 2.0 still follows the core ideas of Echo, but Echo2 provides a vivid user interface through its new AJAX presentation layer engine and also improves overall performance and usability.

3. The performance and ease of use of Echo3 have been greatly improved, and the official version has not yet been released.

Extended information:

ECHO system command

Function description: Display text.

Syntax: echo [-ne][string] or echo [--help][--version]

Additional note: echo will send the input string to the standard output. The output strings are separated by whitespace characters and a newline is added at the end.

Parameters: -n Do not automatically wrap the line at the end

-e If the following characters appear in the string, they will be specially processed and will not be output as ordinary text:

\a emits a warning sound;

\b deletes the previous character;

\c does not add a newline symbol at the end;

\f breaks a newline but the cursor still stays on Original position;

\n Line break and the cursor moves to the beginning of the line;

\r The cursor moves to the beginning of the line, but no line break;

\t Insert tab;

\v is the same as \f;

\\ inserts the \ character;

\nnn inserts the ASCII character represented by nnn (octal);

- -help Display help

--version Display version information

The echo instructions supported by each shell may be different.

-n Do not output the last \n

-eExplain escape characters

-EDo not interpret escape characters

Example: echo "i am a boy" // After execution, i am a boy

i am a boy

will be printed.

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