What is C_lflag?

c_iflag and c_oflag contain flags that affect the processing of input and output, respectively. c_cflag we will mostly ignore, as it contains settings that relate to the control of modems and serial lines that are mostly irrelevant these days. c_lflag is perhaps the most interesting of the flag values.

How do I turn off canonical mode?

1. Turn off canonical mode. There is an ICANON flag that allows us to turn off canonical mode.
2. Turn off Ctrl-C and Ctrl-Z signals.
3. Disable Ctrl-S and Ctrl-Q.
4. Disable Ctrl-V.
5. Fix Ctrl-M.
6. Turn off all output processing.
7. Miscellaneous flags.
8. A timeout for read()

What is RAW mode terminal?

A terminal port in raw mode disables all of that processing. In raw mode, characters are directly read from and written to the device without any translation or interpretation by the operating system.

What is noncanonical mode?

In noncanonical input processing mode, characters are not grouped into lines, and ERASE and KILL processing is not performed. The granularity with which bytes are read in noncanonical input mode is controlled by the MIN and TIME settings. See Noncanonical Input.