<!doctype linuxdoc system>

<article>
<title>cc65 function reference
<author>Ullrich von Bassewitz, <htmlurl url="mailto:uz@cc65.org" name="uz@cc65.org">
<date>07.11.2002

<abstract>
cc65 is a C compiler for 6502 based systems. This function reference describes
the available C functions supplied by the library.
</abstract>

<!-- Table of contents -->
<toc>

<!-- Begin the document -->

<sect>Introduction<p>

cc65 is a C compiler for 6502 based systems. It implements a subset of the ISO
C standard plus additional functions specially crafted for 6502 systems or
just some of the supported machines. This function refrence describes the
available functions together with any limitations.

<bf/Note:/ Standard C functions are listed here, but not described in detail.
Since these functions behave identical on all standard compliant systems, they
are described in any book covering standard C.

Each entry for a function contains a detailed description

<quote>
<descrip>
<tag/Function/Summary of what <bf/function/ does.
<tag/Header/The header file that contains the declaration.
<tag/Declaration/Describes the needed header files and declaration of the
function.
<tag/Description/Description of the function.
<tag/Limits/Limits.
<tag/Availability/The availability of the function.
<tag/See also/Other related functions.
<tag/Example/A piece of actual code using the function.
</descrip>
</quote>


<sect>Functions by header file<p>

<sect1><tt/6502.h/<label id="6502.h"><p>

<itemize>
<item><ref id="BRK" name="BRK">
<item><ref id="CLI" name="CLI">
<item><ref id="SEI" name="SEI">
<!-- <item><ref id="_sys" name="_sys"> -->
<!-- <item><ref id="getcpu" name="getcpu"> -->
<!-- <item><ref id="reset_brk" name="reset_brk"> -->
<!-- <item><ref id="set_brk" name="set_brk"> -->
</itemize>


<sect1><tt/assert.h/<label id="assert.h"><p>

<itemize>
<item><ref id="assert" name="assert">
</itemize>


<sect1><tt/conio.h/<label id="conio.h"><p>

<itemize>
<item><ref id="bgcolor" name="bgcolor">
<item><ref id="bordercolor" name="bordercolor">
<item><ref id="cclear" name="cclear">
<item><ref id="cclearxy" name="cclearxy">
<item><ref id="cgetc" name="cgetc">
<item><ref id="chline" name="chline">
<item><ref id="chlinexy" name="chlinexy">
<item><ref id="clrscr" name="clrscr">
<!-- <item><ref id="cprintf" name="cprintf"> -->
<!-- <item><ref id="cputc" name="cputc"> -->
<!-- <item><ref id="cputcxy" name="cputcxy"> -->
<!-- <item><ref id="cputs" name="cputs"> -->
<!-- <item><ref id="cputsxy" name="cputsxy"> -->
<item><ref id="cursor" name="cursor">
<item><ref id="cvline" name="cvline">
<item><ref id="cvlinexy" name="cvlinexy">
<item><ref id="gotox" name="gotox">
<item><ref id="gotoxy" name="gotoxy">
<item><ref id="gotoy" name="gotoy">
<item><ref id="kbhit" name="kbhit">
<item><ref id="revers" name="revers">
<item><ref id="screensize" name="screensize">
<item><ref id="textcolor" name="textcolor">
<!-- <item><ref id="vcprintf" name="vcprintf"> -->
<item><ref id="wherex" name="wherex">
<item><ref id="wherey" name="wherey">
</itemize>


<sect1><tt/ctype.h/<label id="ctype.h"><p>

<itemize>
<item><ref id="isalnum" name="isalnum">
<item><ref id="isalpha" name="isalpha">
<item><ref id="isascii" name="isascii">
<item><ref id="isblank" name="isblank">
<item><ref id="iscntrl" name="iscntrl">
<item><ref id="isdigit" name="isdigit">
<item><ref id="isgraph" name="isgraph">
<item><ref id="islower" name="islower">
<item><ref id="isprint" name="isprint">
<item><ref id="ispunct" name="ispunct">
<item><ref id="isspace" name="isspace">
<item><ref id="isupper" name="isupper">
<item><ref id="isxdigit" name="isxdigit">
<item><ref id="tolower" name="tolower">
<item><ref id="toupper" name="toupper">
</itemize>


<sect1><tt/stdlib.h/<label id="stdlib.h"><p>

<itemize>
<item><ref id="abort" name="abort">
<item><ref id="atexit" name="atexit">
<item><ref id="exit" name="exit">
</itemize>




<sect>Alphabetical function reference<p>

<sect1>BRK<label id="BRK"><p>

<quote>
<descrip>
<tag/Function/Insert a 6502 BRK instrunction into the code.
<tag/Header/<tt/<ref id="6502.h" name="6502.h">/
<tag/Declaration/<tt/void BRK (void);/
<tag/Description/The function will insert a 6502 BRK instruction into the code
which may be used to trigger a debugger.
<tag/Limits/The function is actually a macro. The inserted instruction may lead
to unexpected results if no debugger is present.
<tag/Availability/cc65
<tag/See also/
<ref id="CLI" name="CLI">,
<ref id="SEI" name="SEI">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>CLI<label id="CLI"><p>

<quote>
<descrip>
<tag/Function/Insert a 6502 CLI instrunction into the code.
<tag/Header/<tt/<ref id="6502.h" name="6502.h">/
<tag/Declaration/<tt/void CLI (void);/
<tag/Description/The function will insert a 6502 CLI instruction into the code,
so interrupts are disabled. Note that non maskable interrupts cannot be
disabled.
<tag/Limits/The function is actually a macro. Disabling interrupts may lead to
unexpected results.
<tag/Availability/cc65
<tag/See also/
<ref id="BRK" name="BRK">,
<ref id="SEI" name="SEI">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>SEI<label id="SEI"><p>

<quote>
<descrip>
<tag/Function/Insert a 6502 SEI instrunction into the code.
<tag/Header/<tt/<ref id="6502.h" name="6502.h">/
<tag/Declaration/<tt/void SEI (void);/
<tag/Description/The function will insert a 6502 SEI instruction into the code,
so interrupts are enabled. Enabling interrupts has no effects if they are
already enabled (the default).
<tag/Limits/The function is actually a macro.
<tag/Availability/cc65
<tag/See also/
<ref id="BRK" name="BRK">,
<ref id="CLI" name="CLI">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>abort<label id="abort"><p>

<quote>
<descrip>
<tag/Function/Terminates a program abnormally.
<tag/Header/<tt/<ref id="stdlib.h" name="stdlib.h">/
<tag/Declaration/<tt/void abort (void);/
<tag/Description/<tt/abort/ writes a termination message on stderr, then
terminates the program with an exit code of 3.
<tag/Availability/ISO 9899
<tag/See also/
<ref id="assert" name="assert">,
<ref id="exit" name="exit">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>assert<label id="assert"><p>

<quote>
<descrip>
<tag/Function/Test a condition and possibly abort.
<tag/Header/<tt/<ref id="assert.h" name="assert.h">/
<tag/Declaration/<tt/void assert (int cond);/
<tag/Description/<tt/assert/ is a macro that expands to a <tt/id/
statement. If the condition evaluates t zero (false), assert prints a message
on stderr and aborts the program.
<tag/Limits/The function is actually a macro.
<tag/Availability/ISO 9899
<tag/See also/
<ref id="abort" name="abort">,
<ref id="exit" name="exit">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>atexit<label id="atexit"><p>

<quote>
<descrip>
<tag/Function/Register an exit function.
<tag/Header/<tt/<ref id="stdlib.h" name="stdlib.h">/
<tag/Declaration/<tt/int __fastcall__ atexit (void (*exitfunc) (void));/
<tag/Description/<tt/atexit/ registers the function pointed to by
<tt/exitfunc/ as an exit function. Exit functions are called when the program
terminates, they are called in LIFO order (the last function registered is
called first). <tt/atexit/ returns zero on success and a nonzero value on 
failure.
<tag/Limits/A maximum of 5 exit functions can be registered. There is no way
to unregister an exit function. The function is only available as fastcall
function, so it may only be used in presence of a prototype.
<tag/Availability/ISO 9899
<tag/See also/
<ref id="abort" name="abort">,
<ref id="exit" name="exit">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>bgcolor<label id="bgcolor"><p>

<quote>
<descrip>
<tag/Function/Set the background text color.
<tag/Header/<tt/<ref id="conio.h" name="conio.h">/
<tag/Declaration/<tt/unsigned char __fastcall__ bgcolor (unsigned char color);/
<tag/Description/The function will set a new background text color. It returns
the old (current) background color.
<tag/Limits/Background colors are system dependent. The function may have no effect
on systems where the background color cannot be changed. The function is only
available as fastcall function, so it may only be used in presence of a
prototype.
<tag/Availability/cc65
<tag/See also/
<ref id="bordercolor" name="bordercolor">,
<ref id="textcolor" name="textcolor">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>bordercolor<label id="bordercolor"><p>

<quote>
<descrip>
<tag/Function/Set the border (frame) color.
<tag/Header/<tt/<ref id="conio.h" name="conio.h">/
<tag/Declaration/<tt/unsigned char __fastcall__ bordercolor (unsigned char color);/
<tag/Description/The function will set a new border color. It returns the old
(current) border color.
<tag/Limits/Border colors are system dependent. The function may have no effect
on systems where the border color cannot be changed. The function is only
available as fastcall function, so it may only be used in presence of a
prototype.
<tag/Availability/cc65
<tag/See also/
<ref id="bgcolor" name="bgcolor">,
<ref id="textcolor" name="textcolor">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>cclear<label id="cclear"><p>

<quote>
<descrip>
<tag/Function/Clear part of a line (write a given amount of spaces).
<tag/Header/<tt/<ref id="conio.h" name="conio.h">/
<tag/Declaration/<tt/void __fastcall__ cclear (unsigned char length);/
<tag/Description/The function clears part of a line by writing <tt/length/
spaces in the current text color.
<tag/Limits/The function is only available as fastcall function, so it may
only be used in presence of a prototype.
<tag/Availability/cc65
<tag/See also/
<ref id="cclearxy" name="cclearxy">,
<ref id="clrscr" name="clrscr">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>cclearxy<label id="cclearxy"><p>

<quote>
<descrip>
<tag/Function/Clear part of a line (write a given amount of spaces) starting
at a specific screen position.
<tag/Header/<tt/<ref id="conio.h" name="conio.h">/
<tag/Declaration/<tt/void __fastcall__ cclearxy (unsigned char length);/
<tag/Description/The function moves the cursor to a specific position, and
will then clear part of the line by writing <tt/length/ spaces in the current
text color.
<tag/Limits/The function is only available as fastcall function, so it may
only be used in presence of a prototype.
<tag/Availability/cc65
<tag/See also/
<ref id="cclear" name="cclear">,
<ref id="clrscr" name="clrscr">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>cgetc<label id="cgetc"><p>

<quote>
<descrip>
<tag/Function/Read a character from the keyboard.
<tag/Header/<tt/<ref id="conio.h" name="conio.h">/
<tag/Declaration/<tt/char cgetc (void);/
<tag/Description/The function reads a character from the keyboard. If there is
no character available, <tt/cgetc/ waits until the user presses a key. If the
cursor is enabled by use of the <tt/cursor/ function, a blinking cursor is
displayed while waiting.
<tag/Limits/If the system supports a keyboard buffer, <tt/cgetc/ will fetch a
key from this buffer and wait only if the buffer is empty.
<tag/Availability/cc65
<tag/See also/
<ref id="cursor" name="cursor">,
<ref id="kbhit" name="kbhit">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>chline<label id="chline"><p>

<quote>
<descrip>
<tag/Function/Output a horizontal line in text mode.
<tag/Header/<tt/<ref id="conio.h" name="conio.h">/
<tag/Declaration/<tt/void __fastcall__ chline (unsigned char length);/
<tag/Description/The function outputs a horizontal line with the given length
starting at the current cursor position.
<tag/Limits/The character used to draw the horizontal line is system dependent.
If available, a line drawing character is used. Drawing a line that is partially
off screen leads to undefined behaviour. The function is only available
as fastcall function, so it may only be used in presence of a prototype.
<tag/Availability/cc65
<tag/See also/
<ref id="chlinexy" name="chlinexy">,
<ref id="cvline" name="cvline">,
<ref id="cvlinexy" name="cvlinexy">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>chlinexy<label id="chlinexy"><p>

<quote>
<descrip>
<tag/Function/Output a horizontal line at a given position in text mode.
<tag/Header/<tt/<ref id="conio.h" name="conio.h">/
<tag/Declaration/<tt/void __fastcall__ chlinexy (unsigned char x, unsigned char y, unsigned char length);/
<tag/Description/The function outputs a horizontal line with the given length
starting at a given position.
<tag/Limits/The character used to draw the horizontal line is system dependent.
If available, a line drawing character is used. Drawing a line that is partially
off screen leads to undefined behaviour. The function is only available
as fastcall function, so it may only be used in presence of a prototype.
<tag/Availability/cc65
<tag/See also/
<ref id="chline" name="chline">,
<ref id="cvline" name="cvline">,
<ref id="cvlinexy" name="cvlinexy">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>clrscr<label id="clrscr"><p>

<quote>
<descrip>
<tag/Function/Clear the text screen.
<tag/Header/<tt/<ref id="conio.h" name="conio.h">/
<tag/Declaration/<tt/void clrscr (void);/
<tag/Description/The function clears the text screen and moves the cursor to
the upper left corner.
<tag/Availability/cc65
<tag/See also/
<ref id="cclear" name="cclear">,
<ref id="cclearxy" name="cclearxy">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>cursor<label id="cursor"><p>

<quote>
<descrip>
<tag/Function/Enable/disable a blinking cursor when waiting for keyboard input.
<tag/Header/<tt/<ref id="conio.h" name="conio.h">/
<tag/Declaration/<tt/unsigned char __fastcall__ cursor (unsigned char onoff);/
<tag/Description/If the argument to the function is non zero, a blinking cursor
will be enabled when the <tt/cgetc/ function waits for input from the keyboard.
If the argument is zero, <tt/cgetc/ will wait without a blinking cursor.
<tag/Limits/The function is only available as fastcall function, so it may only
be used in presence of a prototype.
<tag/Availability/cc65
<tag/See also/
<ref id="cgetc" name="cgetc">,
<ref id="kbhit" name="kbhit">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>cvline<label id="cvline"><p>

<quote>
<descrip>
<tag/Function/Output a vertical line in text mode.
<tag/Header/<tt/<ref id="conio.h" name="conio.h">/
<tag/Declaration/<tt/void __fastcall__ cvline (unsigned char length);/
<tag/Description/The function outputs a vertical line with the given length
starting at the current cursor position.
<tag/Limits/The character used to draw the vertical line is system dependent.
If available, a line drawing character is used. Drawing a line that is partially
off screen leads to undefined behaviour. The function is only available
as fastcall function, so it may only be used in presence of a prototype.
<tag/Availability/cc65
<tag/See also/
<ref id="chline" name="chline">,
<ref id="chlinexy" name="chlinexy">,
<ref id="cvlinexy" name="cvlinexy">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>cvlinexy<label id="cvlinexy"><p>

<quote>
<descrip>
<tag/Function/Output a vertical line at a given position in text mode.
<tag/Header/<tt/<ref id="conio.h" name="conio.h">/
<tag/Declaration/<tt/void __fastcall__ cvlinexy (unsigned char x, unsigned char y, unsigned char length);/
<tag/Description/The function outputs a vertical line with the given length
starting at a given position.
<tag/Limits/The character used to draw the vertical line is system dependent.
If available, a line drawing character is used. Drawing a line that is partially
off screen leads to undefined behaviour. The function is only available
as fastcall function, so it may only be used in presence of a prototype.
<tag/Availability/cc65
<tag/See also/
<ref id="chline" name="chline">,
<ref id="chlinexy" name="chlinexy">,
<ref id="cvline" name="cvline">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>exit<label id="exit"><p>

<quote>
<descrip>
<tag/Function/Terminate the program.
<tag/Header/<tt/<ref id="stdlib.h" name="stdlib.h">/
<tag/Declaration/<tt/void __fastcall__ exit (int status);/
<tag/Description/<tt/exit/ terminates the program. The argument specifies the
return code of the program. Before termination, all files are closed, buffered
output is written and any functions registered with <tt/<ref id="atexit"
name="atexit">/ are called. Common values for status are <tt/EXIT_SUCCESS/ and
<tt/EXIT_FAILURE/ which are also defined in <tt/<ref id="stdlib.h"
name="stdlib.h">/.
<tag/Limits/The function is only available as fastcall function, so it may only
be used in presence of a prototype. It depends on the host machine if the
program return code can be evaluated or is ignored.
<tag/Availability/ISO 9899
<tag/See also/
<ref id="abort" name="abort">,
<ref id="exit" name="exit">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>gotox<label id="gotox"><p>

<quote>
<descrip>
<tag/Function/Move the text mode cursor to a new X position.
<tag/Header/<tt/<ref id="conio.h" name="conio.h">/
<tag/Declaration/<tt/void __fastcall__ gotox (unsigned char x);/
<tag/Description/The function moves the text mode cursor to the specified X
position while leaving the Y position untouched. The leftmost position on the
screen has the coordinate 0.
<tag/Limits/The function is only available as fastcall function, so it may
only be used in presence of a prototype. Invalid values for the X position
(out of screen coordinates) may lead to undefined behaviour.
<tag/Availability/cc65
<tag/See also/
<ref id="gotoy" name="gotoy">,
<ref id="gotoxy" name="gotoxy">,
<ref id="wherex" name="wherex">,
<ref id="wherey" name="wherey">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>gotoxy<label id="gotoxy"><p>

<quote>
<descrip>
<tag/Function/Move the text mode cursor to a new position.
<tag/Header/<tt/<ref id="conio.h" name="conio.h">/
<tag/Declaration/<tt/void __fastcall__ gotoxy (unsigned char x, unsigned char y);/
<tag/Description/The function moves the text mode cursor to the specified
position. The leftmost position on the screen has the X coordinate 0, the
topmost line has the Y coordinate 0.
<tag/Limits/The function is only available as fastcall function, so it may
only be used in presence of a prototype. Invalid values for any of both
coordinates (out of screen positions) may lead to undefined behaviour.
<tag/Availability/cc65
<tag/See also/
<ref id="gotox" name="gotox">,
<ref id="gotoy" name="gotoy">,
<ref id="wherex" name="wherex">,
<ref id="wherey" name="wherey">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>gotoy<label id="gotoy"><p>

<quote>
<descrip>
<tag/Function/Move the text mode cursor to a new Y position.
<tag/Header/<tt/<ref id="conio.h" name="conio.h">/
<tag/Declaration/<tt/void __fastcall__ gotoy (unsigned char x);/
<tag/Description/The function moves the text mode cursor to the specified Y
position while leaving the X position untouched. The uppermost position on the
screen has the coordinate 0.
<tag/Limits/The function is only available as fastcall function, so it may
only be used in presence of a prototype. Invalid values for the Y position
(out of screen coordinates) may lead to undefined behaviour.
<tag/Availability/cc65
<tag/See also/
<ref id="gotox" name="gotox">,
<ref id="gotoxy" name="gotoxy">,
<ref id="wherex" name="wherex">,
<ref id="wherey" name="wherey">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>isalnum<label id="isalnum"><p>

<quote>
<descrip>
<tag/Function/Check if a given character is a letter or digit.
<tag/Header/<tt/<ref id="ctype.h" name="ctype.h">/
<tag/Declaration/<tt/int __fastcall__ isalnum (int c);/
<tag/Description/The function returns a value of zero if the given argument
is a letter or digit. The return value is non zero if the character
is anything else.
<tag/Limits/When compiling with <tt/-Os/ the function is actually a macro. The
generated inline sequence will not work correctly for values outside the range
0..255. <bf/Note:/ The constant <tt/EOF/ is not part of this range. The non
inline function may be accessed by <tt/#undef/'ing the macro. When compiling
without <tt/-Os/, the function is only available as fastcall function, so it
may only be used in presence of a prototype.
<tag/Availability/ISO 9899
<tag/See also/
<ref id="isalpha" name="isalpha">,
<ref id="isascii" name="isascii">,
<ref id="isblank" name="isblank">,
<ref id="iscntrl" name="iscntrl">,
<ref id="isdigit" name="isdigit">,
<ref id="isgraph" name="isgraph">,
<ref id="islower" name="islower">,
<ref id="isprint" name="isprint">,
<ref id="ispunct" name="ispunct">,
<ref id="isspace" name="isspace">,
<ref id="isupper" name="isupper">,
<ref id="isxdigit" name="isxdigit">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>isalpha<label id="isalpha"><p>

<quote>
<descrip>
<tag/Function/Check if a given character is a letter.
<tag/Header/<tt/<ref id="ctype.h" name="ctype.h">/
<tag/Declaration/<tt/int __fastcall__ isalpha (int c);/
<tag/Description/The function returns a value of zero if the given argument
is a letter. The return value is non zero if the character is anything else.
<tag/Limits/When compiling with <tt/-Os/ the function is actually a macro. The
generated inline sequence will not work correctly for values outside the range
0..255. <bf/Note:/ The constant <tt/EOF/ is not part of this range. The non
inline function may be accessed by <tt/#undef/'ing the macro. When compiling
without <tt/-Os/, the function is only available as fastcall function, so it
may only be used in presence of a prototype.
<tag/Availability/ISO 9899
<tag/See also/
<ref id="isalnum" name="isalnum">,
<ref id="isascii" name="isascii">,
<ref id="isblank" name="isblank">,
<ref id="iscntrl" name="iscntrl">,
<ref id="isdigit" name="isdigit">,
<ref id="isgraph" name="isgraph">,
<ref id="islower" name="islower">,
<ref id="isprint" name="isprint">,
<ref id="ispunct" name="ispunct">,
<ref id="isspace" name="isspace">,
<ref id="isupper" name="isupper">,
<ref id="isxdigit" name="isxdigit">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>isascii<label id="isascii"><p>

<quote>
<descrip>
<tag/Function/Check if a given character is in the ASCII (0..127) range.
<tag/Header/<tt/<ref id="ctype.h" name="ctype.h">/
<tag/Declaration/<tt/int __fastcall__ isascii (int c);/
<tag/Description/The function returns a value of zero if the given argument
is in the range 0..127 (the range of valid ASCII characters) and a non zero
value if not.
<tag/Limits/When compiling with <tt/-Os/ the function is actually a macro. The
generated inline sequence will not work correctly for values outside the range
0..255. <bf/Note:/ The constant <tt/EOF/ is not part of this range. The non
inline function may be accessed by <tt/#undef/'ing the macro. When compiling
without <tt/-Os/, the function is only available as fastcall function, so it
may only be used in presence of a prototype.
<tag/Availability/ISO 9899
<tag/See also/
<ref id="isalnum" name="isalnum">,
<ref id="isalpha" name="isalpha">,
<ref id="isblank" name="isblank">,
<ref id="iscntrl" name="iscntrl">,
<ref id="isdigit" name="isdigit">,
<ref id="isgraph" name="isgraph">,
<ref id="islower" name="islower">,
<ref id="isprint" name="isprint">,
<ref id="ispunct" name="ispunct">,
<ref id="isspace" name="isspace">,
<ref id="isupper" name="isupper">,
<ref id="isxdigit" name="isxdigit">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>isblank<label id="isblank"><p>

<quote>
<descrip>
<tag/Function/Check if a given character is a space or tab.
<tag/Header/<tt/<ref id="ctype.h" name="ctype.h">/
<tag/Declaration/<tt/int __fastcall__ isblank (int c);/
<tag/Description/The function returns a value of zero if the given argument
is a blank or space character. The return value is non zero if the character
is anything else.
<tag/Limits/When compiling with <tt/-Os/ the function is actually a macro. The
generated inline sequence will not work correctly for values outside the range
0..255. <bf/Note:/ The constant <tt/EOF/ is not part of this range. The non
inline function may be accessed by <tt/#undef/'ing the macro. When compiling
without <tt/-Os/, the function is only available as fastcall function, so it
may only be used in presence of a prototype.
<tag/Availability/cc65
<tag/See also/
<ref id="isalnum" name="isalnum">,
<ref id="isalpha" name="isalpha">,
<ref id="isascii" name="isascii">,
<ref id="iscntrl" name="iscntrl">,
<ref id="isdigit" name="isdigit">,
<ref id="isgraph" name="isgraph">,
<ref id="islower" name="islower">,
<ref id="isprint" name="isprint">,
<ref id="ispunct" name="ispunct">,
<ref id="isspace" name="isspace">,
<ref id="isupper" name="isupper">,
<ref id="isxdigit" name="isxdigit">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>iscntrl<label id="iscntrl"><p>

<quote>
<descrip>
<tag/Function/Check if a given character is a control character.
<tag/Header/<tt/<ref id="ctype.h" name="ctype.h">/
<tag/Declaration/<tt/int __fastcall__ iscntrl (int c);/
<tag/Description/The function returns a value of zero if the given argument
is a control character. The return value is non zero if the character
is anything else.
<tag/Limits/When compiling with <tt/-Os/ the function is actually a macro. The
generated inline sequence will not work correctly for values outside the range
0..255. <bf/Note:/ The constant <tt/EOF/ is not part of this range. The non
inline function may be accessed by <tt/#undef/'ing the macro. When compiling
without <tt/-Os/, the function is only available as fastcall function, so it
may only be used in presence of a prototype.
<tag/Availability/ISO 9899
<tag/See also/
<ref id="isalnum" name="isalnum">,
<ref id="isalpha" name="isalpha">,
<ref id="isascii" name="isascii">,
<ref id="isblank" name="isblank">,
<ref id="isdigit" name="isdigit">,
<ref id="isgraph" name="isgraph">,
<ref id="islower" name="islower">,
<ref id="isprint" name="isprint">,
<ref id="ispunct" name="ispunct">,
<ref id="isspace" name="isspace">,
<ref id="isupper" name="isupper">,
<ref id="isxdigit" name="isxdigit">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>isdigit<label id="isdigit"><p>

<quote>
<descrip>
<tag/Function/Check if a given character is a digit.
<tag/Header/<tt/<ref id="ctype.h" name="ctype.h">/
<tag/Declaration/<tt/int __fastcall__ isdigit (int c);/
<tag/Description/The function returns a value of zero if the given argument
is a digit. The return value is non zero if the character is anything else.
<tag/Limits/When compiling with <tt/-Os/ the function is actually a macro. The
generated inline sequence will not work correctly for values outside the range
0..255. <bf/Note:/ The constant <tt/EOF/ is not part of this range. The non
inline function may be accessed by <tt/#undef/'ing the macro. When compiling
without <tt/-Os/, the function is only available as fastcall function, so it
may only be used in presence of a prototype.
<tag/Availability/ISO 9899
<tag/See also/
<ref id="isalnum" name="isalnum">,
<ref id="isalpha" name="isalpha">,
<ref id="isascii" name="isascii">,
<ref id="isblank" name="isblank">,
<ref id="iscntrl" name="iscntrl">,
<ref id="isgraph" name="isgraph">,
<ref id="islower" name="islower">,
<ref id="isprint" name="isprint">,
<ref id="ispunct" name="ispunct">,
<ref id="isspace" name="isspace">,
<ref id="isupper" name="isupper">,
<ref id="isxdigit" name="isxdigit">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>isgraph<label id="isgraph"><p>

<quote>
<descrip>
<tag/Function/Check if a given character is a printable character (except
space).
<tag/Header/<tt/<ref id="ctype.h" name="ctype.h">/
<tag/Declaration/<tt/int __fastcall__ isgraph (int c);/
<tag/Description/The function returns a value of zero if the given argument
is a printable character with the exception of space. The return value is non
zero if the character is anything else.
<tag/Limits/When compiling with <tt/-Os/ the function is actually a macro. The
generated inline sequence will not work correctly for values outside the range
0..255. <bf/Note:/ The constant <tt/EOF/ is not part of this range. The non
inline function may be accessed by <tt/#undef/'ing the macro. When compiling
without <tt/-Os/, the function is only available as fastcall function, so it
may only be used in presence of a prototype.
<tag/Availability/ISO 9899
<tag/See also/
<ref id="isalnum" name="isalnum">,
<ref id="isalpha" name="isalpha">,
<ref id="isascii" name="isascii">,
<ref id="isblank" name="isblank">,
<ref id="iscntrl" name="iscntrl">,
<ref id="isdigit" name="isdigit">,
<ref id="islower" name="islower">,
<ref id="isprint" name="isprint">,
<ref id="ispunct" name="ispunct">,
<ref id="isspace" name="isspace">,
<ref id="isupper" name="isupper">,
<ref id="isxdigit" name="isxdigit">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>islower<label id="islower"><p>

<quote>
<descrip>
<tag/Function/Check if a given character is a lower case letter.
<tag/Header/<tt/<ref id="ctype.h" name="ctype.h">/
<tag/Declaration/<tt/int __fastcall__ islower (int c);/
<tag/Description/The function returns a value of zero if the given argument
is a lower case letter. The return value is non zero if the character is
anything else.
<tag/Limits/When compiling with <tt/-Os/ the function is actually a macro. The
generated inline sequence will not work correctly for values outside the range
0..255. <bf/Note:/ The constant <tt/EOF/ is not part of this range. The non
inline function may be accessed by <tt/#undef/'ing the macro. When compiling
without <tt/-Os/, the function is only available as fastcall function, so it
may only be used in presence of a prototype.
<tag/Availability/ISO 9899
<tag/See also/
<ref id="isalnum" name="isalnum">,
<ref id="isalpha" name="isalpha">,
<ref id="isascii" name="isascii">,
<ref id="isblank" name="isblank">,
<ref id="iscntrl" name="iscntrl">,
<ref id="isdigit" name="isdigit">,
<ref id="isgraph" name="isgraph">,
<ref id="isprint" name="isprint">,
<ref id="ispunct" name="ispunct">,
<ref id="isspace" name="isspace">,
<ref id="isupper" name="isupper">,
<ref id="isxdigit" name="isxdigit">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>isprint<label id="isprint"><p>

<quote>
<descrip>
<tag/Function/Check if a given character is a printable character.
<tag/Header/<tt/<ref id="ctype.h" name="ctype.h">/
<tag/Declaration/<tt/int __fastcall__ isprint (int c);/
<tag/Description/The function returns a value of zero if the given argument
is a printable character (this includes the space character). The return value
is non zero if the character is anything else.
<tag/Limits/When compiling with <tt/-Os/ the function is actually a macro. The
generated inline sequence will not work correctly for values outside the range
0..255. <bf/Note:/ The constant <tt/EOF/ is not part of this range. The non
inline function may be accessed by <tt/#undef/'ing the macro. When compiling
without <tt/-Os/, the function is only available as fastcall function, so it
may only be used in presence of a prototype.
<tag/Availability/ISO 9899
<tag/See also/
<ref id="isalnum" name="isalnum">,
<ref id="isalpha" name="isalpha">,
<ref id="isascii" name="isascii">,
<ref id="isblank" name="isblank">,
<ref id="iscntrl" name="iscntrl">,
<ref id="isdigit" name="isdigit">,
<ref id="isgraph" name="isgraph">,
<ref id="islower" name="islower">,
<ref id="ispunct" name="ispunct">,
<ref id="isspace" name="isspace">,
<ref id="isupper" name="isupper">,
<ref id="isxdigit" name="isxdigit">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>ispunct<label id="ispunct"><p>

<quote>
<descrip>
<tag/Function/Check if a given character is a printable character but not a
space or an alphanumeric character.
<tag/Header/<tt/<ref id="ctype.h" name="ctype.h">/
<tag/Declaration/<tt/int __fastcall__ ispunct (int c);/
<tag/Description/The function returns a value of zero if the given argument
is a printable character, but not a space or anything alphanumeric. The return
value is non zero if the character is anything else.
<tag/Limits/When compiling with <tt/-Os/ the function is actually a macro. The
generated inline sequence will not work correctly for values outside the range
0..255. <bf/Note:/ The constant <tt/EOF/ is not part of this range. The non
inline function may be accessed by <tt/#undef/'ing the macro. When compiling
without <tt/-Os/, the function is only available as fastcall function, so it
may only be used in presence of a prototype.
<tag/Availability/ISO 9899
<tag/See also/
<ref id="isalnum" name="isalnum">,
<ref id="isalpha" name="isalpha">,
<ref id="isascii" name="isascii">,
<ref id="isblank" name="isblank">,
<ref id="iscntrl" name="iscntrl">,
<ref id="isdigit" name="isdigit">,
<ref id="isgraph" name="isgraph">,
<ref id="islower" name="islower">,
<ref id="isprint" name="isprint">,
<ref id="isspace" name="isspace">,
<ref id="isupper" name="isupper">,
<ref id="isxdigit" name="isxdigit">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>isspace<label id="isspace"><p>

<quote>
<descrip>
<tag/Function/Check if a given character is a a white-space character.
<tag/Header/<tt/<ref id="ctype.h" name="ctype.h">/
<tag/Declaration/<tt/int __fastcall__ isspace (int c);/
<tag/Description/The function returns a value of zero if the given argument
is a white space character. The return value is non zero if the character is
anything else. The standard white space characters are: space, formfeed ('\f'),
newline ('\n'), carriage return ('\r'), horizontal tab ('\t'), and vertical tab
('\v').
<tag/Limits/When compiling with <tt/-Os/ the function is actually a macro. The
generated inline sequence will not work correctly for values outside the range
0..255. <bf/Note:/ The constant <tt/EOF/ is not part of this range. The non
inline function may be accessed by <tt/#undef/'ing the macro. When compiling
without <tt/-Os/, the function is only available as fastcall function, so it
may only be used in presence of a prototype.
<tag/Availability/ISO 9899
<tag/See also/
<ref id="isalnum" name="isalnum">,
<ref id="isalpha" name="isalpha">,
<ref id="isascii" name="isascii">,
<ref id="isblank" name="isblank">,
<ref id="iscntrl" name="iscntrl">,
<ref id="isdigit" name="isdigit">,
<ref id="isgraph" name="isgraph">,
<ref id="islower" name="islower">,
<ref id="isprint" name="isprint">,
<ref id="ispunct" name="ispunct">,
<ref id="isupper" name="isupper">,
<ref id="isxdigit" name="isxdigit">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>isupper<label id="isupper"><p>

<quote>
<descrip>
<tag/Function/Check if a given character is an upper case letter.
<tag/Header/<tt/<ref id="ctype.h" name="ctype.h">/
<tag/Declaration/<tt/int __fastcall__ isupper (int c);/
<tag/Description/The function returns a value of zero if the given argument
is an upper case letter. The return value is non zero if the character is
anything else.
<tag/Limits/When compiling with <tt/-Os/ the function is actually a macro. The
generated inline sequence will not work correctly for values outside the range
0..255. <bf/Note:/ The constant <tt/EOF/ is not part of this range. The non
inline function may be accessed by <tt/#undef/'ing the macro. When compiling
without <tt/-Os/, the function is only available as fastcall function, so it
may only be used in presence of a prototype.
<tag/Availability/ISO 9899
<tag/See also/
<ref id="isalnum" name="isalnum">,
<ref id="isalpha" name="isalpha">,
<ref id="isascii" name="isascii">,
<ref id="isblank" name="isblank">,
<ref id="iscntrl" name="iscntrl">,
<ref id="isdigit" name="isdigit">,
<ref id="isgraph" name="isgraph">,
<ref id="islower" name="islower">,
<ref id="isprint" name="isprint">,
<ref id="ispunct" name="ispunct">,
<ref id="isspace" name="isspace">,
<ref id="isxdigit" name="isxdigit">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>isxdigit<label id="isxdigit"><p>

<quote>
<descrip>
<tag/Function/Check if a given character is a hexadecimal digit.
<tag/Header/<tt/<ref id="ctype.h" name="ctype.h">/
<tag/Declaration/<tt/int __fastcall__ isxdigit (int c);/
<tag/Description/The function returns a value of zero if the given argument
is a hexadecimal digit (0..9, a..f and A..F). The return value is non zero
if the character is anything else.
<tag/Limits/When compiling with <tt/-Os/ the function is actually a macro. The
generated inline sequence will not work correctly for values outside the range
0..255. <bf/Note:/ The constant <tt/EOF/ is not part of this range. The non
inline function may be accessed by <tt/#undef/'ing the macro. When compiling
without <tt/-Os/, the function is only available as fastcall function, so it
may only be used in presence of a prototype.
<tag/Availability/ISO 9899
<tag/See also/
<ref id="isalnum" name="isalnum">,
<ref id="isalpha" name="isalpha">,
<ref id="isascii" name="isascii">,
<ref id="isblank" name="isblank">,
<ref id="iscntrl" name="iscntrl">,
<ref id="isdigit" name="isdigit">,
<ref id="isgraph" name="isgraph">,
<ref id="islower" name="islower">,
<ref id="isprint" name="isprint">,
<ref id="ispunct" name="ispunct">,
<ref id="isspace" name="isspace">,
<ref id="isupper" name="isupper">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>kbhit<label id="kbhit"><p>

<quote>
<descrip>
<tag/Function/Check if there's a key waiting in the keyboard buffer.
<tag/Header/<tt/<ref id="conio.h" name="conio.h">/
<tag/Declaration/<tt/unsigned char kbhit (void);/
<tag/Description/The function returns a value of zero if there is no character
waiting to be read from the keyboard. It returns non zero otherwise.
<tag/Limits/If the system does not support a keyboard buffer (most systems
do), the function is rather useless.
<tag/Availability/cc65
<tag/See also/
<ref id="cgetc" name="cgetc">,
<ref id="cursor" name="cursor">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>revers<label id="revers"><p>

<quote>
<descrip>
<tag/Function/Control revers character display.
<tag/Header/<tt/<ref id="conio.h" name="conio.h">/
<tag/Declaration/<tt/unsigned char __fastcall__ revers (unsigned char onoff);/
<tag/Description/If the argument is non zero, the function enables reverse
character display. If the argument is zero, reverse character display is
switched off. The old value of the setting is returned.
<tag/Limits/The function may not be supported by the hardware, in which case
the call is ignored. The function is only available as fastcall function, so it
may only be used in presence of a prototype.
<tag/Availability/cc65
<tag/See also/
<ref id="textcolor" name="textcolor">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>screensize<label id="screensize"><p>

<quote>
<descrip>
<tag/Function/Return the dimensions of the text mode screen.
<tag/Header/<tt/<ref id="conio.h" name="conio.h">/
<tag/Declaration/<tt/void __fastcall__ screensize (unsigned char* x, unsigned char* y);/
<tag/Description/The function returns the dimensions of the text mode screen.
<tag/Limits/The function is only available as fastcall function, so it may only
be used in presence of a prototype.
<tag/Availability/cc65
<tag/See also/
<ref id="gotox" name="gotox">,
<ref id="gotoxy" name="gotoxy">,
<ref id="gotoy" name="gotoy">,
<ref id="wherex" name="wherex">,
<ref id="wherey" name="wherey">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>textcolor<label id="textcolor"><p>

<quote>
<descrip>
<tag/Function/Set the text color.
<tag/Header/<tt/<ref id="conio.h" name="conio.h">/
<tag/Declaration/<tt/unsigned char __fastcall__ textcolor (unsigned char color);/
<tag/Description/The function will set a new text color. It returns the old
(current) text color. Text output using any <tt/conio.h/ function will use
the color set by this function.
<tag/Limits/Text colors are system dependent. The function may have no effect
on systems where the text color cannot be changed. The function is only
available as fastcall function, so it may only be used in presence of a
prototype.
<tag/Availability/cc65
<tag/See also/
<ref id="bgcolor" name="bgcolor">,
<ref id="bordercolor" name="bordercolor">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>tolower<label id="tolower"><p>

<quote>
<descrip>
<tag/Function/Convert a character into its lower case representation.
<tag/Header/<tt/<ref id="ctype.h" name="ctype.h">/
<tag/Declaration/<tt/int __fastcall__ tolower (int c);/
<tag/Description/The function returns the given character converted to lower
case. If the given character is not a letter, it is returned unchanged.
<tag/Limits/The function is only available as fastcall function, so it may
only be used in presence of a prototype.
<tag/Availability/ISO 9899
<tag/See also/
<ref id="islower" name="islower">,
<ref id="isupper" name="isupper">,
<ref id="toupper" name="toupper">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>toupper<label id="toupper"><p>

<quote>
<descrip>
<tag/Function/Convert a character into its upper case representation.
<tag/Header/<tt/<ref id="ctype.h" name="ctype.h">/
<tag/Declaration/<tt/int __fastcall__ toupper (int c);/
<tag/Description/The function returns the given character converted to upper
case. If the given character is not a letter, it is returned unchanged.
<tag/Limits/The function is only available as fastcall function, so it may
only be used in presence of a prototype.
<tag/Availability/ISO 9899
<tag/See also/
<ref id="islower" name="islower">,
<ref id="isupper" name="isupper">,
<ref id="tolower" name="tolower">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>wherex<label id="wherex"><p>

<quote>
<descrip>
<tag/Function/Return the current X position of the text mode cursor.
<tag/Header/<tt/<ref id="conio.h" name="conio.h">/
<tag/Declaration/<tt/unsigned char wherex (void);/
<tag/Description/The function returns the current X position of the text mode
cursor. Zero is returned for the leftmost screen position.
<tag/Availability/cc65
<tag/See also/
<ref id="gotox" name="gotox">,
<ref id="gotoy" name="gotoy">,
<ref id="gotoxy" name="gotoxy">,
<ref id="wherey" name="wherey">
<tag/Example/Actual code using the function.
</descrip>
</quote>


<sect1>wherey<label id="wherey"><p>

<quote>
<descrip>
<tag/Function/Return the current Y position of the text mode cursor.
<tag/Header/<tt/<ref id="conio.h" name="conio.h">/
<tag/Declaration/<tt/unsigned char wherey (void);/
<tag/Description/The function returns the current Y position of the text mode
cursor. Zero is returned for the uppermost screen position.
<tag/Availability/cc65
<tag/See also/
<ref id="gotox" name="gotox">,
<ref id="gotoy" name="gotoy">,
<ref id="gotoxy" name="gotoxy">,
<ref id="wherex" name="wherex">
<tag/Example/Actual code using the function.
</descrip>
</quote>


</article>


