Will using this code cause problems? reading keyboard...

[ronin]

I seek the advice of the professional programmers yet again. I'm working on a bit of a text editor. Since I've never taken any data structures classes, nor have I worked with massive amounts of data, I like to know if this sort of coding would cause random errors or other undesired results.

unsigned key1, key2;

key1 = getch();

if(key1 == 0)
{
      key2 = getch();
      switch(key2)
      {
            /* process whatever special key */
      }
}

else
{
     key2 = 0;  /* just in case */
     key1 = (char)key1;

     putchar(key1) /* echo the input at current cursor pos */
}

I tried that _bios_keybrd stuff, but it took way too much code and was too cumbersome to deal with. Then I found this sort of thing doing a search on the board. I tried it and liked the results. Any comments would be greatly appreciated.

TIA

[quzah]

What are you trying to do actually with this bit of code?

Here:

if(key1 == 0)

This is the decimal value of zero, not the character that represents zero. Is this what you want?

key1 = (char)key1;

putchar(key1) /* echo the input at current cursor pos */

There is no point in doing the first of those two lines. You can do the same thing in a single line:

putchar( (char) key1 );

Incidently, 'putchar' takes an integer as its argument.

Quzah.

[ronin]

Originally posted by quzah
What are you trying to do actually with this bit of code?

Here:

if(key1 == 0)

This is the decimal value of zero, not the character that represents zero. Is this what you want?

I am after the decimal value. I need to scan for keys like function keys, arrow keys etc. I believe getch() will return 0 when a special key is pressed followed by that key's scan code. Is this not right?

Say the user presses the up arrow key. key1 will have the 0 and key2 will get the 72. I'm looking to find a way to process the keyboard without having to use the bios or int 16h directly

key1 = (char)key1;

putchar(key1) /* echo the input at current cursor pos */

There is no point in doing the first of those two lines. You can do the same thing in a single line:

putchar( (char) key1 );

Incidently, 'putchar' takes an integer as its argument.

Quzah.

Thanks for that condensed form of putchar, but I posted that in a mad rush before my login timed out :P

The goal in this madness is to read the scan code. I'll convert to printable chars later in the process, and if there is a special key in key2, then I'll process the particular key in a function. This is for a dos program. No win api stuff for me. : )

Thanks for the reply quzah.

[quzah]

If you enable cookies in your login options you won't time out any more.

Quzah. (busy at work right now)

[ronin]

I'm too paranoid for that.