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Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	1	<HTML>
				2	<HEAD>
				3	<TITLE>Using Python on the Macintosh</TITLE>
				4	</HEAD>
				5	<BODY>
				6	<H1>Using Python on the Macintosh</H1>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	7	<HR>
				8
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	9	This document is an introduction to using Python on the Apple
				10	Macintosh. It does not introduce the language itself, for this you
				11	should refer to the <A
				12	HREF="http://www.python.org/doc/tut/tut.html">Python Tutorial</A> by
				13	Guido van Rossum. This guide more-or-less replaces chapter two of the
				14	tutorial, and provides some additional material. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	15
Jack Jansen	0836542	1996-04-19 15:56:08 +0000	[diff] [blame]	16	There is currently no good tutorial for the mac-specific features of
				17	Python, but to whet your appetite: it has interfaces to many MacOS
				18	toolboxes (quickdraw, sound, quicktime, open scripting, etc) and
				19	various portable toolboxes are available too (Tk, stdwin, complex
				20	numbers, image manipulation, etc). Some <A HREF="index.html">
				21	annotated sample programs</A> are available to give you an idea of
				22	Python's power. <P>
				23
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	24	The document refers to Python 1.3.3 or higher, some of the features
				25	(like setting applet options) will not work in earlier versions of
				26	Python. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	27
				28	<h2>Invoking the interpreter</h2>
				29
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	30	The name of the interpreter may differ on different installations: it
				31	may be called <CODE>Python</CODE>, <CODE>PythonPPC</CODE> (for powerpc
				32	macs) or <CODE>Python68K</CODE> (indeed, for 68K macs). It will always
				33	be recognizable by the "16 ton" icon, though. You start the
Jack Jansen	0836542	1996-04-19 15:56:08 +0000	[diff] [blame]	34	interpreter in interactive mode by double-clicking its icon: <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	35
				36	<img src="html.icons/python.gif"><p>
				37
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	38	This should give you a text window with an informative version string
				39	and a prompt, something like the following:
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	40	<PRE>
				41	Python 1.3.3 (Apr 7 1996) [CW PPC w/GUSI]
				42	Copyright 1991-1995 Stichting Mathematisch Centrum, Amsterdam
				43	>>>
				44	</PRE>
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	45	The version string tells you the version of Python, whether it was
				46	built for PPC or 68K macs and possibly some options used to build the
				47	interpreter. If you find a bug or have a question about how the
				48	interpreter works it is a good idea to include the version information
				49	in your message. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	50
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	51	At the prompt you can type interactive python commands. See the
				52	tutorial for more information. The interactive window works
				53	more-or-less like a Communication Toolbox or Telnet window: you type
				54	commands at the bottom and terminate them with the <EM>[return]</EM>
				55	or <EM>[enter]</EM> key. Interpreter feedback also appears at the
				56	bottom of the window, and the contents scroll as output is added. You
				57	can use copy and paste in the normal way, but be sure to paste only at
				58	the bottom of the document.
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	59
				60	<h2>Creating Python scripts</h2>
				61
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	62	The Python interpreter works in a way that is different from what you
				63	would expect of a macintosh program: the interpreter is just that: an
				64	interpreter. There is no builtin editor or other development
				65	support. Hence, to create a Python script you need an external text
				66	editor. For a first script you can use any editor that can create
				67	plain, unstyled text files, such as <CODE>SimpleText</CODE>. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	68
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	69	For more serious scripts, though, it is advisable to use a programmers
				70	editor, such as <CODE>BBEdit</CODE> or <CODE>Alpha</CODE>. BBEdit is
				71	my favorite: it comes in a commercial version but also in a
				72	fully-functional free version <CODE>BBEdit Lite</CODE>. You can
				73	download it from the <A HREF="http://www.barebones.com/">BareBones</A>
				74	site. The free version will probably provide all the functionality
				75	you will ever need. Besides the standard edit facilities it has
				76	multi-file searches and many other goodies that can be very handy when
				77	editing programs. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	78
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	79	After you have created your script in the editor of your choice you
				80	drop it on the interpreter. This will start the interpreter executing
				81	the script, again with a console window in which the output appears
				82	and in which you can type input if the script requires it. Normally
				83	the interpreter will close the window and quit as soon as the script
				84	is done executing, see below under <A HREF="#startup">startup
				85	options</A> for a way to change this. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	86
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	87	It is a good idea to have the names of all your scripts end in
				88	<CODE>.py</CODE>. While this is not necessary for standalone scripts
				89	it is needed for modules, and it is probably a good idea to start the
				90	habit now. <p>
				91
				92	If you do not like to start the Python interpreter afresh for each
				93	edit-run cycle you can use the <CODE>import</CODE> statement and
				94	<CODE>reload()</CODE> function to speed things up in some cases. Here
				95	is Guido's original comment for how to do this, from the 1.1 release
				96	notes: <P>
				97
Jack Jansen	0836542	1996-04-19 15:56:08 +0000	[diff] [blame]	98	<BLOCKQUOTE>
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	99
				100	Make sure the program is a module file (filename must be a Python
				101	identifier followed by '<CODE>.py</CODE>'). You can then import it
				102	when you test it for the first time. There are now three
				103	possibilities: it contains a syntax error; it gets a runtime error
				104	(unhandled exception); or it runs OK but gives wrong results. (If it
				105	gives correct results, you are done testing and don't need to read the
				106	rest of this paragraph. :-) Note that the following is not
				107	Mac-specific -- it's just that on UNIX it's easier to restart the
				108	entire script so it's rarely useful. <P>
				109
				110	Recovery from a syntax error is easy: edit the file and import it
				111	again. <P>
				112
				113	Recovery from wrong output is almost as easy: edit the file and,
				114	instead of importing it, call the function <CODE>reload()</CODE> with
				115	the module name as argument (e.g., if your module is called
				116	<CODE>foo</CODE>, type <CODE>reload(foo)</CODE>). <P>
				117
				118	Recovery from an exception is trickier. Once the syntax is correct, a
				119	'module' entry is placed in an internal table, and following import
				120	statements will not re-read the file, even if the module's
				121	initialization terminated with an error (one reason why this is done
				122	is so that mutually recursive modules are initialized only once). You
				123	must therefore force re-reading the module with <CODE>reload()</CODE>,
				124	however, if this happens the first time you try to import the module,
				125	the import statement itself has not completed, and your workspace does
				126	not know the module name (even though the internal table of moduesl
				127	does!). The trick is to first import the module again, then reload
				128	it. For instance, <CODE>import foo; reload(foo)</CODE>. Because the
				129	module object already exists internally, the import statement does not
				130	attempt to execute the module again -- it just places it in your
Jack Jansen	0836542	1996-04-19 15:56:08 +0000	[diff] [blame]	131	workspace. </BLOCKQUOTE>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	132
				133	<h2>Clickable python scripts</h2>
				134
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	135	If you create your script with the correct creator and type, creator
				136	<CODE>'Pyth'</CODE> and type <CODE>'TEXT'</CODE>, you can double-click
				137	your script and it will automatically invoke the interpreter. If you
				138	use BBEdit you can tell it about the Python file type by adding it to
				139	the "file types" sections of the preferences. Then, if you save a file
				140	for the first time you can tell BBEdit to save the file as a Python
				141	script through the "options" choice of the save dialog. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	142
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	143	The <CODE>Scripts</CODE> folder contains a script
				144	<CODE>fixfiletypes</CODE> that will recursively traverse a folder and
				145	set the correct creator and type for all files ending in
				146	<CODE>.py</CODE>. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	147
Jack Jansen	0836542	1996-04-19 15:56:08 +0000	[diff] [blame]	148	<BLOCKQUOTE>
				149	Older releases of Python used the creator code
				150	<CODE>'PYTH'</CODE> in stead of <CODE>'Pyth'</CODE>. If you still have
				151	older Python sources on your system and named them with
				152	<CODE>'.py'</CODE> extension the <CODE>fixfiletypes</CODE> script will
				153	correct them.
				154	</BLOCKQUOTE>
				155
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	156	<h2>Interaction with the user</h2>
				157
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	158	Normally, the interpreter will check for user input (mouse clicks,
				159	keyboard input) every once in a while, so it is possible to switch to
				160	other applications while a script runs. It is also possible to
				161	interrupt the interpreter with the standard command-period keypress,
				162	this will raise the <CODE>KeyboardInterrupt</CODE> exception. Scripts
				163	may, however, turn off this behaviour to facilitate their own event
				164	handling. Such scripts can only be killed with the
				165	command-option-escape shortcut.
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	166
				167	<h2><A NAME="startup">startup options</A></h2>
				168
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	169	If the <EM>option</EM> key is depressed when Python starts executing
				170	the interpreter will bring up an options dialog thru which you can
				171	influence the way the interpreter behaves. Keep the option key
				172	depressed until the dialog comes up. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	173
				174	<img src="html.icons/options.gif"><p>
				175
				176	The options modify the interpreters behaviour in the following way:
				177	<ul>
				178	<li> the interpreter goes to interactive mode (in stead of
				179	exiting) after a script has terminated normally,
				180	<li> for every module imported a line is printed telling you where the
				181	module was loaded from,
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	182	<li> do not print the values of expressions executed as statements in
				183	an interactive python,
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	184	<li> do not buffer stdout and stderr,
				185	<li> print some debugging output during the parsing phase,
				186	<li> keep the output window open when a script terminates.
				187	</ul>
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	188	In addition, you can enter a unix-style command line which is passed
				189	to the script in <CODE>sys.argv</CODE>. Sys.argv[0] is always the name
				190	of the script being executed, additional values can be passed
				191	here. Quoting works as expected. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	192
Jack Jansen	22fa642	1996-09-05 15:15:59 +0000	[diff] [blame^]	193	<BLOCKQUOTE>
				194	<EM>Warning:</EM> redirecting standard input or standard output in the
				195	command-line dialog does not work. This is due to circumstances beyond my
				196	control, hence I cannot say when this will be fixed.
				197	</BLOCKQUOTE>
				198
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	199	The default options are also settable on a system-wide basis, see the
				200	section on <A HREF="#preferences">editing preferences</A>. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	201
				202	<h2>Module search path</h2>
				203
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	204	The module search path, <CODE>sys.path</CODE>, contains the folders
				205	python will search when you import a module. The path is settable on a
				206	system-wide basis (see the preferences section), and normally
				207	comprises the current folder (where the script lives), the
				208	<CODE>Lib</CODE> folder and some of its subfolders and possibly some
				209	more. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	210
				211	<h2>Working folder</h2>
				212
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	213	The unix concept of a <I>working directory</I> does not translate
				214	directly to a similar concept on the Macintosh. To facilitate easy
				215	porting and the use of relative pathnames in scripts the interpreter
				216	simulates a working directory. When a script is started the initial
				217	working directory is the folder where the script lives. In case of an
				218	interactive interpreter the working directory is the folder where the
				219	interpreter lives. <P>
				220
				221	By the way: the "standard file" folder, the folder that is presented
				222	to the user initially for an <I>open</I> or <I>save</I> dialog, does
				223	<EM>not</EM> follow the Python working directory. Which folder is
				224	initially shown to the user is usually one of (a) the application
				225	folder, (b) the "Documents" folder or (c) the folder most recently
				226	used for such a dialog (in any Python program). This is standard MacOS
				227	behaviour, so don't blame Python for it. The exact behaviour is
				228	settable through a control panel since System 7.5.
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	229
				230	<h2>Interactive startup file</h2>
				231
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	232	If the folder containing the interpreter contains a file named
				233	<CODE>PythonStartup</CODE> this file is executed when you start an
				234	interactive interpreter. In this file you could import modules you
				235	often use and other such things. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	236
				237
				238	<h2>Compiled python scripts</h2>
				239
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	240	Once a python module has been imported the interpreter creates a
				241	compiled version which is stored in a file with the ".py" extension
				242	replaced by ".pyc". These compiled files, with creator
				243	<CODE>'Pyth'</CODE> and type <CODE>'PYC '</CODE> load faster when
				244	imported (because they do not have to be parsed). The <CODE>Lib</CODE>
				245	folder contains a script <CODE>compileall.py</CODE>, running this
				246	script will cause all modules along the python search path to be
				247	precompiled, which will speed up your programs. Compiled files are
				248	also double-clickable. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	249
				250	<h2>Python resources</h2>
				251
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	252	MacPython has the ability to collect a number of compiled modules
				253	together in the resource fork of a single file. This feature is useful
				254	if you distribute a python program and want to minimize clutter: you
				255	can put all the needed modules in a single file (which could even be
				256	the interpreter itself). <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	257
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	258	If the module search path contains a filename as one of its entries
				259	(as opposed to a folder name, which is the normal case) this file will
				260	be searched for a resource with type <CODE>'PYC '</CODE> and a name
				261	matching the module being imported. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	262
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	263	The <CODE>scripts</CODE> folder contains a script
				264	<CODE>PackLibDir</CODE> which will convert a number of modules (or
				265	possibly a complete subtree full of modules) into such a resource
				266	file.
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	267
				268	<h2><A NAME="preferences">Setting interpreter preferences</A></h2>
				269
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	270	The python interpreter keeps a preferences file in the standard
				271	location in the system folder. In this preferences file it remembers
				272	the default module search path and the default settings for the
				273	runtime options. The preferences are settable via
				274	<CODE>EditPythonPrefs</CODE>. For PPC python this is a standalone
				275	program living in the main Python folder, for 68K python it is a
				276	script in the <CODE>Scripts</CODE> folder. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	277
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	278	The interface to edit the preferences is rather clunky for the current
				279	release. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	280
				281	<img src="html.icons/preferences.gif"><p>
				282
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	283	In the editable text field at the top you enter the initial module
				284	search path, using newline as a separator. There are two special
				285	values you can use here: an initial substring <CODE>$(PYTHON)</CODE>
				286	will expand to the Python home folder and a value of
				287	<CODE>$(APPLICATION)</CODE> will expand to the the python application
				288	itself. Note that the text field may extend "beyond the bottom" even
				289	though it does not have a scroll bar. Using the arrow keys works,
				290	though.<p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	291
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	292	The Python home folder $(PYTHON) is initially, when you execute the
				293	interpreter for the first time, set to the folder where the
				294	interpreter lives. You can change it here. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	295
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	296	Finally, you can set the default startup options here, through a
				297	sub-dialog.
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	298
				299	<h2>Applets</h2>
				300
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	301	An applet is a fullblown application written in Python, similar to an
				302	AppleScript applet (and completely different from a Java
				303	applet). Applets are currently only supported on PowerPC macintoshes,
				304	and are created using the <CODE>mkapplet</CODE> program. You create an
				305	applet by dropping the python source script onto mkapplet. The
				306	<CODE>Demo</CODE> folder contains an example of a more involved applet
				307	with its own resource file, etc. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	308
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	309	Note that while an applet behaves as a fullblown Macintosh application
				310	it is not self-sufficient, so distributing it to a machine without an
				311	installed Python interpreter will not work: it needs the shared python
				312	execution engine <CODE>PythonCore</CODE>, and probably various modules
				313	from the Lib and PlugIns folders. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	314
				315	<h2>Customizing applets</h2>
				316
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	317	Applets can have their own settings for the startup options and module
				318	search path. Dropping an applet on the <CODE>EditPythonPrefs</CODE>
				319	application allows you to set these, in the same way as
				320	double-clicking EditPythonPrefs allows you to set the system-wide
				321	defaults. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	322
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	323	Actually, not only applets but also the interpreter itself can have
				324	non-default settings for path and options. If you make a copy of the
				325	interpreter and drop this copy onto EditPythonPrefs you will have an
				326	interpreter that has a different set of default settings.
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	327
				328	<h2>Where to go from here</h2>
				329
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	330	The previously mentioned <A
				331	HREF="http://www.python.org/doc/tut/tut.html">Python Tutorial</A> is
				332	an excellent place to start reading if you have never used Python
				333	before. Other documentation such as the library reference manual is
				334	indexed at the <A HREF="http://www.python.org/doc/">Python
				335	Documentation</A> page. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	336
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	337	There are some <A HREF="index.html">annotated sample programs</A>
				338	available that show some mac-specific issues, like use of various
				339	toolboxes and creation of Python applets. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	340
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	341	Finally, the <CODE>Demo</CODE> folder in the Macintosh distribution
				342	contains a number of other example programs. Most of these are only
				343	very lightly documented, but they may help you to understand some
				344	aspects of using Python. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	345
				346	The best way to contact fellow Macintosh Python programmers is to join
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	347	the MacPython Special Interest Group mailing list. Send a message with
				348	"info" in the body to <A
				349	HREF="mailto:pythonmac-sig-request@python.org">pythonmac-sig-request@python.org</A>
				350	or view the <A
				351	HREF="http://www.python.org/sigs/pythonmac-sig/">Pythonmac SIG
				352	page</A> on the <A HREF="http://www.python.org">www.python.org</A> WWW
				353	server. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	354
				355	<h2>Troubleshooting</h2>
				356
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	357	Python is a rather safe language, and hence it should be difficult to
				358	crash the interpreter of the system with a Python script. There is an
				359	exception to this rule, though: the modules that interface to the
				360	system toolboxes (windowing, quickdraw, etc) do very little error
				361	checking and therefore a misbehaving program using these modules may
				362	indeed crash the system. Such programs are unfortunately rather
				363	difficult to debug, since the crash does not generate the standard
				364	Python stack trace, obviously, and since debugging print statements
				365	will often interfere with the operation of the program. There is
				366	little to do about this currently. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	367
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	368	Probably the most common cause of problems with modules ported from
				369	other systems is the Mac end-of-line convention. Where unix uses
Jack Jansen	d9585c9	1996-05-07 15:28:20 +0000	[diff] [blame]	370	linefeed, 0x0a, to separate lines the mac uses carriage return,
				371	0x0d. To complicate matters more a lot of mac programming editors like
Jack Jansen	bd9565a	1996-04-15 12:25:44 +0000	[diff] [blame]	372	BBEdit and emacs will work happily with both conventions, so the file
				373	will appear to be correct in the editor but cause strange errors when
				374	imported. BBEdit has a popup menu which allows you to inspect (and
				375	set) the end-of-line convention used in a file. <p>
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	376
Jack Jansen	024a387	1996-07-18 16:07:05 +0000	[diff] [blame]	377	<h2>Where to go from here</h2>
				378
				379	The next section to check out is the <a href="index.html">annotated sample programs</a>.<p>
				380
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	381	<HR>
				382	<A HREF="http://www.cwi.nl/~jack">Jack Jansen</A>,
Jack Jansen	22fa642	1996-09-05 15:15:59 +0000	[diff] [blame^]	383	<A HREF="mailto:jack@cwi.nl">jack@cwi.nl</A>, 05-Sep-1996.
Jack Jansen	5f962c2	1996-04-10 14:52:59 +0000	[diff] [blame]	384
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