Specific language features of MacPerl				Matthias Neeracher 27Dec94

This file describes differences between MacPerl and a typical Unix perl
implementation. Much of this information can also be found at the end of
PerlHelp. If you have 411, search for PerlÉMacintoshÉExtensions.

1. VARIA

All time related functions measure time in seconds from 1904, not 1970 as in
Unix.

"\n" on a Mac means ASCII 13, as opposed to Unix, where it means ASCII 10.

Pathnames are specified as:

volume:folder:file				for absolute pathnames
:folder:file						for relative pathnames
:file									for relative pathnames
file									for relative pathnames

MacPerl has a limited capability to handle constructs like `command` or
open(F, "|command"), if you are the lucky owner of ToolServer. Additionally, whether
you have toolserver or not, `pwd` and `Directory` (case is significant) always return
the current directory, followed by a newline.

2. SOCKETS

MacPerl has more Socket families than Unix Perl. Additionally, there is a call
choose() to allow the user to interactively specify addresses or file names. As
there are lots of rather complicated data types, there is a library header "GUSI.ph"
which defines packing/unpacking procedures.

Choose() is called as follows:

&MacPerl'Choose(DOMAIN,TYPE,PROMPT,CONSTRAINT,FLAGS,DEFAULT)
&MacPerl'Choose(DOMAIN,TYPE,PROMPT,CONSTRAINT,FLAGS)
&MacPerl'Choose(DOMAIN,TYPE,PROMPT,CONSTRAINT)
&MacPerl'Choose(DOMAIN,TYPE,PROMPT)
         Puts up a modal dialog prompting the user to choose an address. 
         DOMAIN specifies the communication domain, like for socket().
         TYPE may be used by future communication domains to further 
         differentiate within a domain, but is ignored by current domains. 
         PROMPT is a message that will appear in the dialog. CONSTRAINT may 
         be set to a suitable packed value to restrict the types of acceptable
         addresses.

         Examples:

         require "GUSI.ph";
         
         $file = 
            &MacPerl'Choose(
               &GUSI'AF_FILE, 0, "", 
               &GUSI'pack_sa_constr_file("OBJ ", "TEXT"));
                            
                            Return the full pathname of an existing text
                            or MPW object file.
         
         $dir = &MacPerl'Choose(&GUSI'AF_FILE, 0, "", "", &GUSI'CHOOSE_DIR);

                            Return the full pathname of an existing directory.
                            
         $file = 
            &MacPerl'Choose(
               &GUSI'AF_FILE, 0, "", "", 
               &GUSI'CHOOSE_NEW + &GUSI'CHOOSE_DEFAULT, "yo");

                            Return the pathname of a new file to be created.
									 
Socket families are:

Internet:

Packing addresses:	&GUSI'pack_sockaddr_in(family, address, port)
Unpacking addresses:	(family, address, port) = &GUSI'unpack_sockaddr_in(addr)
Choose:					Not available.

Unix:

Packing addresses:	&GUSI'pack_sockaddr_un(family, path)
Unpacking addresses:	(family, path) = &GUSI'unpack_sockaddr_un(addr)
Choose:					choose(&GUSI'AF_UNIX, 0, "", "", 0, "");
							looks up an existing address.
							choose(
								&GUSI'AF_UNIX, 0, "Yes ?", "", 
								&GUSI'CHOOSE_NEW + &GUSI'CHOOSE_DEFAULT, "yo");
							creates a new address.
							No constraints may be specified.

Appletalk (ADSP):

Packing addresses:	&GUSI'pack_sockaddr_atlk(family, net, node, socket) 	(numerical)
							&GUSI'pack_sockaddr_atlk_sym(family, obj, type, zone)	(symbolic)
Unpacking addresses:	(family, net, node, socket) = &GUSI'unpack_sockaddr_atlk(addr)
							(family, obj, type, zone) = &GUSI'unpack_sockaddr_atlk_sym(addr)
Choose:					choose(&GUSI'AF_APPLETALK, 0, "Eh ?", 
								&GUSI'pack_sa_constr_atlk("LaserWriter", "GorillaWriter"),
								0, "");
							looks up an existing address.
							New addresses may not currently be created with choose.

PPC Toolbox:

Packing addresses:	&GUSI'pack_sockaddr_ppc(family, type, name, porttype)
Unpacking addresses:	Not available.
Choose:					choose(&GUSI'AF_PPC, 0, "Eh ?", 
								&GUSI'pack_sa_constr_ppc("Gonkulator"),
								0, "");
							looks up an existing address.
							New addresses may not currently be created with choose.


3. ADDITIONAL FUNCTIONS AVAILABLE IN MACPERL

&MacPerl'Answer(PROMPT)
&MacPerl'Answer(PROMPT,BUTTON1)
&MacPerl'Answer(PROMPT,BUTTON1,BUTTON2)
&MacPerl'Answer(PROMPT,BUTTON1,BUTTON2,BUTTON3)
          Presents to the user a dialog with 1, 2, or 3 buttons. 
          
          Examples:
          
          &MacPerl'Answer("Nunc et in hora mortis nostrae", "Amen");
                              
                            always returns 0.
                            
          &MacPerl'Answer("I refuse");
          
                              is equivalent to &MacPerl'Answer("I refuse", "OK");
          
          &MacPerl'Answer("Delete hard disk ?", "OK", "Cancel");
                  
                            returns 1 for OK, 0 for Cancel
        
          &MacPerl'Answer("Overwrite existig file", "Overwrite", "Skip", "Cancel");
              
                            returns 2 for Overwrite, 1 for Skip, 0 for Cancel
									 
&MacPerl'Ask(PROMPT, DEFAULT)
&MacPerl'Ask(PROMPT)
          Asks the user for a string. A default value may be given. Returns
          undef if the dialog is cancelled.
          
          Example:
          
          $phone = &&MacPerl'Ask("Enter your phone number:");
          $name = &&MacPerl'Ask("Enter your first name", "Bruce");
          
                            Useful for Australian database applications
									 
&MacPerl'Pick(PROMPT, VALUES)
          Asks the user to pick a choice from a list. VALUES is a list of choices. 
          Returns undef if the dialog is cancelled.
          
          Examples:
          
          $color = &MacPerl'Pick("What's your favorite color baby ?", "Red", "Green", "Gold");
			 
&MacPerl'SetFileInfo(CREATOR,TYPE,FILE...)
			Changes the file types and creators of the file(s).

			Examples:

			&MacPerl'SetFileInfo("MPS ", "TEXT", yin, yang);

									Turn yin and yang into MPW text files

&MacPerl'GetFileInfo(FILE)
			In scalar context, returns the file type. In array context, returns
			(creator,type).

			Examples:

			&MacPerl'GetFileInfo(yin);

									Returns "TEXT" or ("MPS ", "TEXT").

&MacPerl'DoAppleScript(SCRIPT)
			Execute an AppleScript script.
			
			Example:
			
			&MacPerl'DoAppleScript(<<END_SCRIPT);
tell application "MacPerl"
	make new Window
	copy "Inserting text the hard way." to character 1 of front Window
end tell
END_SCRIPT

&MacPerl'Reply(ANSWER)
			Reply to current DoScript request. Useful if you are calling Perl 
			scripts from other applications.
			
&MacPerl'Quit(LEVEL)
			If LEVEL is 0, don't quit after ending the script. If 1, quit if 
			running under a runtime version, if 2, always quit. If LEVEL is 3,
			quit if this was the first script to be run since starting MacPerl.

&MacPerl'LoadExternals(LIBFILE)
			Load XCMD and XFCN extensions contained in file LIBFILE, which is searched
			along the same path as it would be for a require. The extensions are made
			accessible in the current package, unless they conatin an explicit package
			name.

&MacPerl'DebugExternals(DEBUGLEVEL)
			If DEBUGLEVEL is 0, don't print any debug information for XCMDs and XFCNs. 
			If 1, print information for unimplemented callbacks. If 2, print 
			informations for all callbacks.

&MacPerl'FAccess(FILE, CMD, ARGS)
			When called from the tool, manipulate various information of files. To 
			get the command constants, it's convenient to require "FAccess.ph".

	$TAB = &MacPerl'FAccess(FILE, &F_GTABINFO)
	&MacPerl'FAccess(FILE, &F_STABINFO, TAB)
			Manipulate tabulator setting (in spaces per tab).
			
	($FONTNAME, $FONTSIZE) = &MacPerl'FAccess(FILE, &F_GFONTINFO)
	$FONTNUM = &MacPerl'FAccess(FILE, &F_GFONTINFO)
	&MacPerl'FAccess(FILE, &F_SFONTINFO, FONT [, SIZE])
			Manipulate font and size information. Both font names and font numbers
			are accepted for F_SFONTINFO; F_GFONTINFO returns a font name in an
			array context, a font number in a scalar context.
			
	($STARTSEL, $ENDSEL, $DISPLAYTOP) = &MacPerl'FAccess(FILE, &F_GSELINFO)
	$STARTSEL = &MacPerl'FAccess(FILE, &F_GSELINFO)
	&MacPerl'FAccess(FILE, &F_SSELINFO, $STARTSEL, $ENDSEL [, $DISPLAYTOP])
			Manipulate the MPW selection of a file.
			
	($LEFT, $TOP, $RIGHT, $BOTTOM) = &MacPerl'FAccess(FILE, &F_GWININFO)
	$TOP = &MacPerl'FAccess(FILE, &F_GWININFO)
	&MacPerl'FAccess(FILE, &F_SWININFO, LEFT, TOP [, RIGHT, BOTTOM])
			Manipulate the window position.

&MacPerl'MakeFSSpec(PATH)
			This command encodes a path name into an encoding (volume #, directory #,
			File name) which is guaranteed to be unique for every file. Don't store
			this encoding between runs of MacPerl!

&MacPerl'MakePath(FSSPEC)
			The inverse of &MacPerl'MakeFSSpec(): turn an encoding into a path name.

&MacPerl'Volumes()
			In scalar context, return the FSSPEC of the startup volume. In list
			context, return FSSPECs of all volumes.

4. MACPERL SPECIFIC LIBRARIES

StandardFile.pl   Calls for standard file dialogs. A very convenient front end
                  for &MacPerl'Choose()
						
FindFolder.pl     Returns the path names of special folders (System, Preferences).

CommConnect.pl    Library for accessing the serial port.

GUSI.ph           Definitions for socket related calls.

FAccess.ph        Definitions for &MacPerl'FAccess() (MPW tool only).