Data commit

Task/Keyboard-input-Flush-the-keyboard-buffer/C/keyboard-input-flush-the-keyboard-buffer-1.c

@@ -0,0 +1,30 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+int main(int argc, char* argv[])
+{
+    // Get a chance to make stdin input buffer dirty.
+    //
+    char text[256];
+    getchar();
+
+    // This DOES NOT WORK properly on all modern systems including Linux & W10.
+    // Obsolete, don't use this. BTW, there is no fpurge in MSVC libs in 2020.
+    //
+    // fflush(stdin);
+
+    // Always works. Readed characters may remain somethere in RAM.
+    //
+    fseek(stdin, 0, SEEK_END);
+
+    // A very dirty solution - an unbuffered stream does not need any flushing.
+    //
+    // setvbuf(stdin, NULL, _IONBF, 0);
+
+    // Now we are able to check if the buffer is really empty.
+    //
+    fgets(text, sizeof(text), stdin);
+    puts(text);
+
+    return EXIT_SUCCESS;
+}

Task/Keyboard-input-Flush-the-keyboard-buffer/C/keyboard-input-flush-the-keyboard-buffer-2.c

@@ -0,0 +1,68 @@
+#include <stdio.h>
+#include <stdio.h>
+#include <termios.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <ctype.h>
+
+void set_mode(int want_key)
+{
+	static struct termios old, new;
+	if (!want_key) {
+		tcsetattr(STDIN_FILENO, TCSANOW, &old);
+		return;
+	}
+
+	tcgetattr(STDIN_FILENO, &old);
+	new = old;
+	new.c_lflag &= ~(ICANON);
+	tcsetattr(STDIN_FILENO, TCSANOW, &new);
+}
+
+int get_key()
+{
+	int c = 0;
+	fd_set fs;
+
+	FD_ZERO(&fs);
+	FD_SET(STDIN_FILENO, &fs);
+	select(STDIN_FILENO + 1, &fs, 0, 0, 0);
+
+	if (FD_ISSET(STDIN_FILENO, &fs)) {
+		c = getchar();
+		set_mode(0);
+	}
+	return c;
+}
+
+int main()
+{
+	int c = 0;
+	while (c != 'n') {
+		set_mode(1);
+
+		/* flush pending input so we won't format the hardrive
+		   because user accidentally typed 'y' before we even prompted */
+		tcflush(STDIN_FILENO, TCIFLUSH);
+
+		printf("Show this prompt again [Yes/No/Ignore you]? ");
+		fflush(stdout);
+
+		switch(c = tolower(get_key())) {
+		case 'y':	putchar('\n');
+				break;
+
+		case 'n':	printf("\nDone\n");
+				break;
+
+		case 'i':	puts("\nI'll ignore keys for 5 seconds");
+				sleep(5);
+				putchar('\n');
+				break;
+		default:
+				puts("\nAssume that was the cat.");
+		}
+	}
+
+	return 0;
+}

Task/Keyboard-input-Flush-the-keyboard-buffer/C/keyboard-input-flush-the-keyboard-buffer-3.c

@@ -0,0 +1,23 @@
+#include <conio.h>
+#include <tchar.h>
+
+// Uses only CRT functions. No need to include 'Windows.h'.
+
+void Kbflush(void)
+{
+    while (_kbhit())
+    {
+        // The _gettch function reads a single character without echoing it. When reading
+        // a function key or an arrow key, it must be called twice; the first call returns
+        // 0x00 or 0xE0 and the second call returns the actual key code. Source: MSDN.
+        int ch = _gettch();
+        if (ch == 0x00 || ch == 0xE0)
+            (void)_gettch();
+    }
+}
+
+int _tmain(void)
+{
+    Kbflush();
+    return 0;
+}