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