Tgetentchar

Tgetentchar is a system call and a function in various programming languages that are used to retrieve a single character from the terminal input. It stands for "get entropy character," but its primary function is to read a character from the standard input, typically the keyboard.

The calling convention for tgetentchar varies across different systems and programming languages. It is generally used as a blocking call, meaning it will wait for the user to type a character before returning. In many implementations, tgetentchar will also modify the state of the terminal, for example, by echoing the input character or waiting for a newline character before returning.

In various programming languages, the system call or function is named differently. For example, in C, the code to read a single character would look something like this: char c; if ((c = getchar())!= EOF) { /* c contains the character entered at the console */ } However, in a calling convention compatible with system calls, this functionality may be referred to as tgetentchar.

Tgetentchar is also commonly used in interactive shell code or programs that need to read input from the user one character at a time, such as games or menu systems. It provides a way to read input immediately as the user types it, rather than waiting for a newline character.

The origin of the term "tgetentchar" is unclear but it likely comes from the term being a system call that reads something from the terminal. Whether it reads a "character" could depend on how one interprets that term. The call is generally blocking, meaning that it will wait for input from the user before returning.