Is there an equivelant for Pascal's readkey; in C or C++?

Question

I am looking for a Console function that waits for the user to press a key. I want it to be like Pascal's readkey; as in a Console Only solution. No GUI library / Graphics Library / Windowing Library / WinApi Calls (Windows). It should be cross-platform and (preferably) part of the C std library or C++ Class Library. So is there any such function / class method etc. ?

Writing multi-language source files is difficult. I suggest you keep each source file in only a single, distinct language — pmg, Sep 18 '11 at 11:37
@Paul: the question is tagged both `C` and `C++`. What I mean is for the OP to study the answers and maintain the `C` solution in its own source file and the `C++` in another source file. If I misunderstood the question and what the OP wants is a single solution that works both in `C` and `C++` I suspect he won't get many answers :-) — pmg, Sep 18 '11 at 11:50
@pmg Sorry I guess I was the one who misunderstood your comment. :) — ApprenticeHacker, Sep 18 '11 at 11:57
Standard C++ has no such solution, but then again. Standard Pascal doesn't have `readkey` either. — MSalters, Sep 19 '11 at 08:50

score 6 · Accepted Answer · answered Sep 18 '11 at 11:36

The C Standard library has no notion of a "keyboard buffer". input/output is mostly line-based (triggered when ENTER is pressed).

You have a few options:

use an external library like ncurses
change the terminal buffering strategy with setvbuf() and use fgetc() (and wait for ENTER if you didn't change the buffering strategy)

score 2 · Answer 2 · answered Sep 18 '11 at 11:37

2

As far as I know there is no portable solution for your item. In windows, you can use the header <conio.h> which has a function called getch() for getting a char directly from the console. If you are in Linux, then you can use the library ncurses.

answered Sep 18 '11 at 11:37

Mythli

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So as you are saying that `getch()` isn't portable across other platforms. So how does `getch()` function behaves if I'm running my C program on Linux/unix. I believe `` header file is part of C standard library which will be available across other platforms too or that is an incorrect assumption? – RBT Sep 21 '16 at 02:58
@RBT `conio.h` is not a part of the standard C. It is not available in *nix. Better follow this thread: [Where is the header file on Linux? Why can't I find ?](https://stackoverflow.com/q/8792317) – brc-dd May 07 '21 at 16:09

Pete Wilson · Answer 3 · 2011-09-18T11:49:11.517

If you're in a Windws run-time environment, you can use the non-standard C function kbhit( ). And there's a C-language Linux equivalent for Windows kbhit( ). The function does just what you want: it will tell you if a keyboard character has been typed without reading the character; or, alternatively, will read and deliver to you one character iff one has been typed. You can find it over here:

http://pwilson.net/sample.html

Scroll down to the paragraph headed "Single-character keyboard input for Linux and Unix"

HTH

score 0 · Answer 4 · edited May 09 '21 at 15:13

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Simple:

getchar();

Literally the equivalent for readkey() in C#.

edited May 09 '21 at 15:13

Lori

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answered May 07 '21 at 14:20

Lorenzo Conti

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`getchar()` requires the user to press ENTER key. I don't think that OP wanted that. – brc-dd May 07 '21 at 16:01

score 0 · Answer 5 · answered Sep 18 '11 at 11:28

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Considered _getch ?

answered Sep 18 '11 at 11:28

Claus Jørgensen

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Is there an equivelant for Pascal's readkey; in C or C++?

5 Answers5