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774 lines
26 KiB
Plaintext
774 lines
26 KiB
Plaintext
<!doctype linuxdoc system>
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<article>
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<title>Apple ][ specific information for cc65
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<author><url url="mailto:ol.sc@web.de" name="Oliver Schmidt">
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<abstract>
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An overview over the Apple ][ runtime system as it is
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implemented for the cc65 C compiler.
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</abstract>
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<!-- Table of contents -->
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<toc>
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<!-- Begin the document -->
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<sect>Overview<p>
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This file contains an overview of the Apple ][ runtime system
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as it comes with the cc65 C compiler. It describes the memory layout,
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Apple ][ specific header files, available drivers, and any
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pitfalls specific to that platform.
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Please note that Apple ][ specific functions are just mentioned
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here, they are described in detail in the separate <url url="funcref.html"
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name="function reference">. Even functions marked as "platform dependent" may
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be available on more than one platform. Please see the function reference for
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more information.
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<sect>Binary format<p>
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The standard binary file format generated by the linker for the
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Apple ][ target is an <url name="AppleSingle"
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url="https://nulib.com/library/AppleSingle_AppleDouble.pdf"> file.
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The default load address is $803.
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<bf/AppleCommander 1.4.0/ or later (available at <url
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url="https://applecommander.github.io/">) includes the option <tt/-as/ that
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allows to put AppleSingle files onto disk images containing DOS 3.3 as well
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as ProDOS 8.
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<sect>Memory layout<p>
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In the standard setup, cc65 generated programs use the memory from
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$803 to $95FF, so 35.5 KB of RAM are available.
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Special locations:
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<descrip>
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<tag/Stack/
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The C runtime stack is located at HIMEM and grows downwards, regardless of
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how your linker config file is setup.
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<tag/Heap/
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The C heap is located at the end of the program and grows towards the C
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runtime stack.
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</descrip><p>
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While running <tt/main()/ the Language Card bank 2 is enabled for read access.
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However while running module constructors the Language Card is disabled.
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Enabling the Language Card allows to use it as additional memory for cc65
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generated code. However code is never automatically placed there. Rather code
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needs to be explicitly placed in the Language Card either per file by compiling
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with <tt/--code-name LC/ or per function by enclosing in <tt/#pragma code-name
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(push, "LC")/ and <tt/#pragma code-name (pop)/. In either case the cc65 runtime
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system takes care of actually moving the code into the Language Card.
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The amount of memory available in the Language Card for generated code depends
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on the <ref id="link-configs" name="linker configuration"> parameters. There are
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several useful settings:
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<descrip>
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<tag>LC address: $D400, LC size: $C00</tag>
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For plain vanilla ProDOS 8 which doesn't actually use the Language Card bank 2
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memory from $D400 to $DFFF. This is the default setting.
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<tag>LC address: $D000, LC size: $1000</tag>
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For ProDOS 8 together with the function <tt/rebootafterexit()/. If a program
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doesn't quit to the ProDOS 8 dispatcher but rather reboots the machine after
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exit then a plain vanilla ProDOS 8 doesn't make use of the Language Card bank
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2 at all.
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<tag>LC address: $D000, LC size: $3000</tag>
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For plain vanilla DOS 3.3 which doesn't make use of the Language Card at all.
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</descrip><p>
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<sect>Linker configurations<label id="link-configs"><p>
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The ld65 linker comes with a default config file for the Apple ][,
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which is used via <tt/-t apple2/.
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The apple2 package comes with additional secondary linker config files, which
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are used via <tt/-t apple2 -C <configfile>/.
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<sect1>default config file (<tt/apple2.cfg/)<label id="apple-def-cfg"><p>
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Default configuration for a binary program.
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Parameters:
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<descrip>
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<tag><tt/STARTADDRESS:/ Program start address</tag>
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Default: $803. Use <tt/-S <addr>/ to set a different start address.
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<tag><tt/__EXEHDR__:/ AppleSingle executable file header</tag>
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Default: Yes. Use <tt/-D __EXEHDR__=0/ to omit the AppleSingle header.
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<tag><tt/__STACKSIZE__:/ C runtime stack size</tag>
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Default: $800. Use <tt/-D __STACKSIZE__=<size>/ to set a different
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stack size.
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<tag><tt/__HIMEM__:/ Highest usable memory address presumed at link time</tag>
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Default: $9600. Use <tt/-D __HIMEM__=<addr>/ to set a different
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highest usable address.
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<tag><tt/__LCADDR__:/ Address of code in the Language Card</tag>
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Default: $D400. Use <tt/-D __LCADDR__=<addr>/ to set a different
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code address.
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<tag><tt/__LCSIZE__:/ Size of code in the Language Card</tag>
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Default: $C00. Use <tt/-D __LCSIZE__=<size>/ to set a different
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code size.
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</descrip><p>
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<sect1><tt/apple2-system.cfg/<label id="apple-sys-cfg"><p>
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Configuration for a system program running on ProDOS 8 and using the memory from
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$2000 to $BEFF.
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Parameters:
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<descrip>
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<tag><tt/__EXEHDR__:/ AppleSingle executable file header</tag>
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Default: Yes. Use <tt/-D __EXEHDR__=0/ to omit the AppleSingle header.
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<tag><tt/__STACKSIZE__:/ C runtime stack size</tag>
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Default: $800. Use <tt/-D __STACKSIZE__=<size>/ to set a different
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stack size.
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<tag><tt/__LCADDR__:/ Address of code in the Language Card</tag>
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Default: $D400. Use <tt/-D __LCADDR__=<addr>/ to set a different
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code address.
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<tag><tt/__LCSIZE__:/ Size of code in the Language Card</tag>
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Default: $C00. Use <tt/-D __LCSIZE__=<size>/ to set a different
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code size.
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</descrip><p>
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<sect1><tt/apple2-hgr.cfg/<p>
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Configuration for a program including a hires page. See <tt>testcode/lib/apple/hgrtest.c</tt>
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for an example of such a program.
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Parameters:
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<descrip>
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<tag><tt/STARTADDRESS:/ Program start address</tag>
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Default: $803. Use <tt/-S <addr>/ to set a different start address.
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<tag><tt/__EXEHDR__:/ AppleSingle executable file header</tag>
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Default: Yes. Use <tt/-D __EXEHDR__=0/ to omit the AppleSingle header.
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<tag><tt/__STACKSIZE__:/ C runtime stack size</tag>
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Default: $800. Use <tt/-D __STACKSIZE__=<size>/ to set a different
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stack size.
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<tag><tt/__HIMEM__:/ Highest usable memory address presumed at link time</tag>
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Default: $9600. Use <tt/-D __HIMEM__=<addr>/ to set a different
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highest usable address.
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<tag><tt/__LCADDR__:/ Address of code in the Language Card</tag>
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Default: $D400. Use <tt/-D __LCADDR__=<addr>/ to set a different
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code address.
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<tag><tt/__LCSIZE__:/ Size of code in the Language Card</tag>
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Default: $C00. Use <tt/-D __LCSIZE__=<size>/ to set a different
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code size.
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</descrip><p>
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<sect1><tt/apple2-overlay.cfg/<p>
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Configuration for an overlay program with up to nine overlays. The overlay files
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don't include the AppleSingle header. See <tt>samples/overlaydemo.c</tt> for more
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information on overlays.
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Parameters:
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<descrip>
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<tag><tt/STARTADDRESS:/ Program start address</tag>
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Default: $803. Use <tt/-S <addr>/ to set a different start address.
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<tag><tt/__EXEHDR__:/ AppleSingle executable file header</tag>
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Default: Yes. Use <tt/-D __EXEHDR__=0/ to omit the AppleSingle header.
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<tag><tt/__STACKSIZE__:/ C runtime stack size</tag>
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Default: $800. Use <tt/-D __STACKSIZE__=<size>/ to set a different
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stack size.
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<tag><tt/__HIMEM__:/ Highest usable memory address presumed at link time</tag>
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Default: $9600. Use <tt/-D __HIMEM__=<addr>/ to set a different
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highest usable address.
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<tag><tt/__LCADDR__:/ Address of code in the Language Card</tag>
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Default: $D400. Use <tt/-D __LCADDR__=<addr>/ to set a different
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code address.
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<tag><tt/__LCSIZE__:/ Size of code in the Language Card</tag>
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Default: $C00. Use <tt/-D __LCSIZE__=<size>/ to set a different
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code size.
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<tag><tt/__OVERLAYSIZE__:/ Size of code in the overlays</tag>
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Default: $1000. Use <tt/-D __OVERLAYSIZE__=<size>/ to set a different
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code size.
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</descrip><p>
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<sect1><tt/apple2-asm.cfg/<p>
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Configuration for an assembler program that doesn't need a special setup.
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Parameters:
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<descrip>
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<tag><tt/STARTADDRESS:/ Program start address</tag>
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Default: $803. Use <tt/-S <addr>/ to set a different start address.
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<tag><tt/__EXEHDR__:/ AppleSingle executable file header</tag>
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Default: No. Use <tt/-u __EXEHDR__ apple2.lib/ to add the AppleSingle header.
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</descrip><p>
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<sect>ProDOS 8 system programs<p>
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ProDOS 8 system programs are always loaded to the start address $2000.
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For cc65 programs this means that the 6 KB from $800 to $2000 are
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by default unused. There are however several options to make use of that memory
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range.
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<sect1>LOADER.SYSTEM<p>
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The easiest (and for really large programs in fact the only) way to have a cc65
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program use the memory from $800 to $2000 is to link it as binary
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(as opposed to system) program using the default linker configuration
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<ref id="apple-def-cfg" name="apple2.cfg"> with <tt/__HIMEM__/ set to $BF00
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and load it with the LOADER.SYSTEM utility. The program then works like a system
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program (i.e. quits to the ProDOS dispatcher).
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Using LOADER.SYSTEM is as simple as copying it to the ProDOS 8 directory of the
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program to load under name <program>.SYSTEM as a system program. For
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example the program <tt/MYPROG/ is loaded by <tt/MYPROG.SYSTEM/. The right
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AppleCommander option to put LOADER.SYSTEM on a ProDOS 8 disk image is <tt/-p/.
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<sect1>Heap<p>
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If the cc65 program can be successfully linked as system program using the linker
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configuration <ref id="apple-sys-cfg" name="apple2-system.cfg">, but
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uses the heap either explicitly or implicitly (i.e. by loading a driver) then
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the memory from $800 to $1FFF can be added to the heap by calling
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<tt/_heapadd ((void *) 0x0800, 0x1800);/ at the beginning of <tt/main()/.
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<sect1>ProDOS 8 I/O buffers<p>
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ProDOS 8 requires for every open file a page-aligned 1 KB I/O buffer. By default
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these buffers are allocated by the cc65 runtime system on the heap using
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<tt/posix_memalign()/. While this is generally the best solution it means quite
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some overhead for (especially rather small) cc65 programs which do open files
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but don't make use of the heap otherwise.
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The apple2 package comes with the alternative ProDOS 8 I/O buffer allocation
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module <tt/apple2-iobuf-0800.o/ which uses the memory between $800 and
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the program start address for the 1 KB I/O buffers. For system programs (with
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start address $2000) this results in up to 6 I/O buffers and thus up to 6
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concurrently open files.
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While using <tt/_heapadd()/ as described in the section above together with the
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default I/O buffer allocation basically yields the same placement of I/O buffers
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in memory the primary benefit of <tt/apple2-iobuf-0800.o/ is a reduction in code
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size - and thus program file size - of more than 1400 bytes.
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Using <tt/apple2-iobuf-0800.o/ is as simple as placing it on the linker command
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line like this:
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<tscreen><verb>
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cl65 -t apple2 -C apple2-system.cfg myprog.c apple2-iobuf-0800.o
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</verb></tscreen>
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<sect>Platform specific header files<p>
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Programs containing Apple ][ specific code may use the
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<tt/apple2.h/ header file.
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<sect1>Apple ][ specific functions<p>
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The functions and variables listed below are special for the Apple ][.
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See the <url url="funcref.html" name="function reference"> for declaration and
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usage.
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<itemize>
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<item>_auxtype
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<item>_dos_type
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<item>_filetype
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<item>_datetime
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<item>beep
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<item>get_ostype
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<item>gmtime_dt
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<item>mktime_dt
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<item>rebootafterexit
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<item>ser_apple2_slot
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<item>tgi_apple2_mix
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</itemize>
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<sect1>Apple IIgs specific functions in accelerator.h<p>
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In addition to those, the <tt/accelerator.h/ header file contains three functions
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to help determine whether the program is running on a IIgs, and change the IIgs
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CPU speed. See the <url url="funcref.html" name="function reference"> for declaration and
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usage.
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<itemize>
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<item>detect_iigs
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<item>get_iigs_speed
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<item>set_iigs_speed
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</itemize>
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<sect1>Hardware access<p>
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There's currently no support for direct hardware access. This does not mean
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you cannot do it, it just means that there's no help.
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<sect>Loadable drivers<p>
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The names in the parentheses denote the symbols to be used for static linking of the drivers.
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<sect1>Graphics drivers<p>
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<descrip>
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<tag><tt/a2.lo.tgi (a2_lo_tgi)/</tag>
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This driver features a resolution of 40×48 with 16 colors.
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The function <tt/tgi_apple2_mix()/ allows to activate 4 lines of text. The
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function clears the corresponding area at the bottom of the screen.
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<tag><tt/a2.hi.tgi (a2_hi_tgi)/</tag>
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This driver features a resolution of 280×192 with 8 colors and two
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hires pages. Note that programs using this driver will have to be linked
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with <tt/-S $4000/ to reserve the first hires page or with <tt/-S $6000/
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to reserve both hires pages.
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The function <tt/tgi_apple2_mix()/ allows to activate 4 lines of text. The
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function doesn't clear the corresponding area at the bottom of the screen.
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In memory constrained situations the memory from $803 to $1FFF
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can be made available to a program by calling <tt/_heapadd ((void *) 0x0803, 0x17FD);/
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at the beginning of <tt/main()/. Doing so is beneficial even if the program
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doesn't use the heap explicitly because loading the driver (and in fact
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already opening the driver file) uses the heap implicitly.
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</descrip><p>
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<sect1>Extended memory drivers<p>
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<descrip>
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<tag><tt/a2.auxmem.emd (a2_auxmem_emd)/</tag>
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Gives access to 47.5 KB RAM (190 pages of 256 bytes each) on an Extended
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80-Column Text Card.
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Note that this driver doesn't check for the actual existence of the memory
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and that it doesn't check for ProDOS 8 RAM disk content!
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</descrip><p>
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<sect1>Joystick drivers<p>
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<descrip>
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<tag><tt/a2.stdjoy.joy (a2_stdjoy_joy)/</tag>
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Supports up to two standard analog joysticks connected to the game port of
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the Apple ][.
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</descrip><p>
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<sect1>Mouse drivers<p>
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<descrip>
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<tag><tt/a2.stdmou.mou (a2_stdmou_mou)/</tag>
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Driver for the AppleMouse II Card. Searches all Apple II slots
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for an AppleMouse II Card compatible firmware. The default bounding
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box is [0..279,0..191].
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Programs using this driver will have to be linked with <tt/-S $4000/
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to reserve the first hires page if they are intended to run on an
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Apple ][ (in contrast to an Apple //e) because the
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AppleMouse II Card firmware writes to the hires page when initializing
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on that machine.
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Note that the Apple ][ default mouse callbacks support text
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mode only.
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</descrip><p>
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<sect1>RS232 device drivers<p>
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<descrip>
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<tag><tt/a2.ssc.ser (a2_ssc_ser)/</tag>
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Driver for the Apple II Super Serial Card.
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The SSC is an extension card for the II, II+, IIe; the Apple //c and //c+ have
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the same hardware and firmware integrated.
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It supports up to 9600 baud, supports no flow control and hardware flow control
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(RTS/CTS) and does interrupt driven receives. Speeds faster than 9600 baud
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aren't reachable because the ROM and ProDOS IRQ handlers are too slow.
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Software flow control (XON/XOFF) is not supported.
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Note that because of the peculiarities of the 6551 chip transmits are not
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interrupt driven, and the transceiver blocks if the receiver asserts
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flow control because of a full buffer.
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Note that using the driver at SER_BAUD_115200 will disable IRQs. It will be up
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to the users to use the serial port, either by re-enabling IRQs themselves,
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or by directly poll-reading the ACIA DATA register without the help of ser_get().
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The driver defaults to slot 2. Call <tt/ser_apple2_slot()/ prior to
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<tt/ser_open()/ in order to select a different slot. <tt/ser_apple2_slot()/
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succeeds for all Apple II slots, but <tt/ser_open()/ fails with
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<tt/SER_ERR_NO_DEVICE/ if there's no SSC firmware found in the selected slot.
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In the Apple //c and //c+, slot 1 is the printer port, and slot 2 is the modem
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port.
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Never call <tt/ser_apple2_slot()/ after <tt/ser_open()/.
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<tag><tt/a2.gs.ser (a2_gs_ser)/</tag>
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Driver for the Apple IIgs serial ports (printer and modem).
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It supports up to 9600 baud, supports no flow control and hardware flow control
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(RTS/CTS) and does interrupt driven receives. Speeds faster than 9600 baud
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aren't reachable because the ROM and ProDOS IRQ handlers are too slow.
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Software flow control (XON/XOFF) is not supported.
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Note that transmits are not interrupt driven, and the transceiver blocks if
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the receiver asserts flow control because of a full buffer.
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The driver defaults to opening the modem port. Calling <tt/ser_apple2_slot()/
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prior to <tt/ser_open()/ allows to select the printer port (1) or the modem
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port (0).
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Never call <tt/ser_apple2_slot()/ after <tt/ser_open()/.
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</descrip><p>
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<sect>Limitations<p>
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<sect1>DOS 3.3<p>
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Although the standard binaries generated by the linker for the Apple ][
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generally run both on DOS 3.3 (with Applesoft BASIC) and on ProDOS 8 (with
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BASIC.SYSTEM) there are some limitations for DOS 3.3:
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<descrip>
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<tag>Disk file I/O</tag>
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There's no disk file I/O support. Any attempt to use it yields an error with
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<tt/errno/ set to <tt/ENOSYS/. This implicitly means that loadable drivers
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are in general not functional as they depend on disk file I/O. Therefore the statically
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linked drivers have to be used instead.
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<tag/Interrupts/
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There's no <tt/interruptor/ support. Any attempt to use it yields the message
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'FAILED TO ALLOC INTERRUPT' on program startup. This implicitly means that
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mouse and RS232 device drivers are not functional as they depend on interrupts.
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</descrip><p>
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<sect1>Direct console I/O<p>
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The Apple ][ has no color text mode. Therefore the functions
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<tt/textcolor()/, <tt/bgcolor()/ and <tt/bordercolor()/ have no effect.
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<sect1>Random number generator<p>
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The random number seed is generated from the time the program waits for user input.
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Therefore it is necessary to wait for at least one user keypress either via Standard
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I/O or via Direct console I/O before initializing the pseudo random number generator.
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<sect1>Realtime clock<p>
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There are several types of realtime clocks. It's not desirable to have specific code
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for all of them. As ProDOS 8 supports file timestamps, realtime clock owners usually
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use ProDOS 8 drivers for their realtime clock. Those drivers read the realtime clock
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and write the result to the date/time location in RAM ($BF90 to $BF93).
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ProDOS 8 reads the date/time from that RAM location. If there's no realtime clock the
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RAM location keeps containing zeros. ProDOS 8 uses those zeros as timestamps and the
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files show up in a directory as <tt/<NO DATE>/.
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There's no common interface to set realtime clocks so if a realtme clock <bf/IS/
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present there's just nothing to do. However, if there's <bf/NO/ realtime clock present,
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the user might very well be interested to "manually" set the RAM location in order to
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have timestamps. But he surely doesn't want to manually set the RAM location over and
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over again. Rather he wants to set it just once after booting ProDOS 8.
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From that perspective it makes most sense to not set both the date and the time but
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rather only set the date and have the time just stay zero. Then files show up in a
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directory as <tt/DD-MON-YY 0:00/.
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So <tt/clock_settime()/ checks if a realtime clock is active. If it is then
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<tt/clock_settime()/ fails with <tt/ERANGE/. Otherwise <tt/clock_settime()/
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sets the date - and completely ignores the time provided as parameter.
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<tt/clock_getres()/ too checks if a realtime clock is active. If it is then
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<tt/clock_getres()/ returns a time resolution of one minute. Otherwise
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<tt/clock_getres()/ presumes that the only one who sets the RAM location is
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<tt/clock_settime()/ and therefore returns a time resolution of one day.
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<sect>Other hints<p>
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<sect1>Passing arguments to the program<p>
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Command line arguments can be passed to <tt/main()/ after BLOAD. Since this is not
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supported by BASIC, the following syntax was chosen:
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<tscreen><verb>
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]CALL2051:REM ARG1 " ARG2 IS QUOTED" ARG3 "" ARG5
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</verb></tscreen>
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<enum>
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<item>Arguments are separated by spaces.
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<item>Arguments may be quoted.
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<item>Leading and trailing spaces around an argument are ignored. Spaces within
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a quoted argument are allowed.
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<item>The first argument passed to <tt/main/ is the program name.
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<item>A maximum number of 10 arguments (including the program name) are
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supported.
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</enum>
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<sect1>Interrupts<p>
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The runtime for the Apple ][ uses routines marked as
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<tt/.INTERRUPTOR/ for ProDOS 8 interrupt handlers. Such routines must be
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written as simple machine language subroutines and will be called
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automatically by the interrupt handler code when they are linked into a
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program. See the discussion of the <tt/.CONDES/ feature in the <url
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url="ca65.html" name="assembler manual">.
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<sect1>ProDOS date/time manipulation<p>
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<descrip>
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The readdir and stat function return ProDOS timestamps in their file
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creation/modification time attributes. You can convert them to more portable
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time representations using either:
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<tag/struct tm/
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<tt/struct tm* __fastcall__ gmtime_dt (const struct datetime* dt);/
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Converts a <tt/struct datetime/ into a <tt/struct tm/. Returns NULL in case
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of error and sets errno.
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<tag/time_t/
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<tt/time_t __fastcall__ mktime_dt (const struct datetime* dt);/
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Parses a <tt/struct datetime/ and returns a UNIX timestamp. Returns 0 on error and
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sets errno.
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</descrip>
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<sect1>DIO<p>
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<descrip>
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<tag/Drive ID/
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The function <url url="dio.html#s1" name="dio_open()"> has the single
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parameter <tt/device/ to identify the device to be opened. Therefore an
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Apple II slot and drive pair is mapped to that <tt/device/ according
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to the formula
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<tscreen>
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device = slot + (drive - 1) * 8
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</tscreen>
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so that for example slot 6 drive 2 is mapped to <tt/device/ 14.
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<tag/Sector count/
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The function <url url="dio.html#s3" name="dio_query_sectcount()"> returns
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the correct sector count for all ProDOS 8 disks. However for any non-ProDOS 8
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disk it simply always returns 280 (which is only correct for a 140 KB disk).
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This condition is indicated by the <tt/_oserror/ value 82.
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</descrip><p>
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<sect1>Specifying file types for fopen<p>
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<descrip>
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<tag>Explanation of File Types</tag>
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ProDOS 8 associates a file type and an auxiliary type with each file.
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These type specifications are separate from the file's name, unlike
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Windows which uses the file name's suffix (a.k.a.
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extension) to specify the file type. For example, <tt/.exe/,
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<tt/.doc/, or <tt/.bat/.
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The ProDOS 8 Machine-Language Interface (MLI) function for creating a
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file require these types to be specified.
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In contrast, the ISO C function <tt/fopen()/ and the POSIX function
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<tt/open()/ have no parameter to specify either a file type or an
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auxiliary type. Therefore, some additional mechanism for specifying
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the file types is needed.
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<tag>Specifying the File Type and Auxiliary Type</tag>
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There are two global variables provided that allow the file type
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and auxiliary type to be specified before a call to <tt/fopen()/
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or <tt/open()/. They are defined in <tt/apple2_filetype.h/:
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<tscreen>
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<verb>
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extern unsigned char _filetype; /* Default: PRODOS_T_BIN */
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extern unsigned int _auxtype; /* Default: 0 */
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</verb>
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</tscreen>
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The header file <tt/apple2_filetype.h/ also defines many values
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that can be used to set these variables. It is included in
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<tt/apple2.h/.
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The global variable <tt/_datetime/ allows the file creation date/time
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to be set before a call to <tt/fopen()/
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or <tt/open()/ that creates the file. It is defined in <tt/apple2.h/:
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<tscreen>
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<verb>
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extern struct datetime _datetime;
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</verb>
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</tscreen>
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<tag>Example</tag>
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A text file cannot be created with just the
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standard C functions because they default to the binary type
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<tt/PRODOS_T_BIN/. The <tt/_filetype/ variable must be set to
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<tt/PRODOS_T_TXT/ to create a text file.
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For a text file,
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<tt/_auxtype/ specifies the record length. A zero record
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length text file is referred to as a sequential text file.
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This is equivalent to text files on
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other operating systems, except that the line terminator is a
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carriage return instead of a line-feed (Linux/BSD/MacOS) or
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carriage return, line-feed pair (Windows).
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The 'sequential' text file terminology is in contrast to a
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'random-access' text file which would
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have a fixed-length, non-zero record length, so that the
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file position of any individual record can be calculated.
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For this example, the
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<tt/_auxtype/ does not need to be set because it defaults to
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the desired value, which is zero. To be more explicit,
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<tt/_auxtype/ can also be set to <tt/PRODOS_AUX_T_TXT_SEQ/
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which is defined as zero.
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<tscreen>
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<verb>
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#include <stdio.h>
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#include <string.h>
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#include <errno.h>
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#include <apple2.h>
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void main(void)
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{
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FILE *out;
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char *name = "MY.FAVS";
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/*-----------------------------*/
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_filetype = PRODOS_T_TXT;
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_auxtype = PRODOS_AUX_T_TXT_SEQ;
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/*-----------------------------*/
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if ((out = fopen(name, "w")) != NULL) {
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fputs("Jorah Mormont\r", out);
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fputs("Brienne of Tarth\r", out);
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fputs("Daenerys Targaryen\r", out);
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fputs("Sandor Clegane\r", out);
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if (fclose(out) == EOF) {
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fprintf(stderr, "fclose failed for %s: %s", name, strerror(errno));
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}
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}
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else {
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fprintf(stderr, "fopen failed for %s: %s", name, strerror(errno));
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}
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}
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</verb>
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</tscreen>
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</descrip><p>
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<sect>License<p>
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This software is provided 'as-is', without any expressed or implied
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warranty. In no event will the authors be held liable for any damages
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arising from the use of this software.
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Permission is granted to anyone to use this software for any purpose,
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including commercial applications, and to alter it and redistribute it
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freely, subject to the following restrictions:
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<enum>
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<item> The origin of this software must not be misrepresented; you must not
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claim that you wrote the original software. If you use this software
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in a product, an acknowledgment in the product documentation would be
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appreciated but is not required.
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<item> Altered source versions must be plainly marked as such, and must not
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be misrepresented as being the original software.
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<item> This notice may not be removed or altered from any source
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distribution.
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</enum>
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</article>
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