BIBTeX change file for Vax/VMS
Modified, 12-Feb-88 by Jerry Leichter for Version .99b
Modified, 15-Apr-88 by Jerry Leichter for Version .99c
Modified, 27-May-88 by Nelson Beebe.  Fixed some spelling errors and typos
	that showed up when the code was woven.  Added support for specifying
	the file name on the command line.
@x
\def\title{\BibTeX\ }
@y
\pageno=\contentspagenumber \advance\pageno by 1
\let\maybe=\iffalse
\def\title{\BibTeX changes for Vax/VMS}
@z

@x
@d banner=='This is BibTeX, Version 0.99c' {printed when the program starts}
@y
@d banner=='This is BibTeX, Vax/VMS Version 0.99c'
@z

@x
@d term_out == tty
@d term_in == tty
@y
@d term_out == output
@d term_in == input
@z

@x
@d print(#) == begin write(log_file,#); write(term_out,#); end
@d print_ln(#) == begin write_ln(log_file,#); write_ln(term_out,#); end
@d print_newline == print_a_newline
				{making this a procedure saves a little space}
@#
@d trace_pr(#) == begin write(log_file,#); end
@d trace_pr_ln(#) == begin write_ln(log_file,#); end
@d trace_pr_newline == begin write_ln(log_file); end

@<Procedures and functions for all file I/O, error messages, and such@>=
procedure print_a_newline;
begin
write_ln(log_file);
write_ln(term_out);
end;
@y
@d print(#) == begin write(log_file,#); write(term_out,#); end
@d print_ln(#) == begin write_ln(log_file,#,chr(13),chr(10));
 write_ln(term_out,#,chr(13),chr(10)); end
@d print_newline == print_a_newline
                                {making this a procedure saves a little space}
@#
@d trace_pr(#) == begin write(log_file,#); end
@d trace_pr_ln(#) == begin write_ln(log_file,#,chr(13),chr(10)); end
@d trace_pr_newline == begin write_ln(log_file,chr(13),chr(10)); end

@<Procedures and functions for all file I/O, error messages, and such@>=
procedure print_a_newline;
begin
write_ln(log_file,chr(13),chr(10));
write_ln(term_out,chr(13),chr(10));
end;
@z

@x
@d othercases == others: {default for cases not listed explicitly}
@y
@d othercases == otherwise {Vax/VMS default for cases not listed
 explicitly}
@z

@x
program BibTEX;			{all files are opened dynamically}
@y
program BibTEX(input,output);
			{all files are opened dynamically}
@z

@x
@<Compiler directives@>=
@{@&$C-,A+,D-@}	 {no range check, catch arithmetic overflow, no debug overhead}
@!debug @{@&$C+,D+@}@+ gubed		{but turn everything on when debugging}
@y
On Vax/VMS, there are no compiler directives that can be introduced in this
way, but we take this opportunity to include a few system-dependent goodies.

@d VAX_text==@= text @>
@d VAX_new==@= new @>
@d VAX_none==@= none @>
@d VAX_word==@= word @>
@d VAX_error==@= error @>
@d VAX_length==@= length @>
@d VAX_syi_sid==@= syi$_sid @>
@d VAX_continue==@= continue @>
@d VAX_external==@= external @>
@d VAX_readonly==@= readonly @>
@d VAX_volatile==@= volatile @>
@d VAX_aligned==@= aligned @>
@d VAX_unsigned==@= unsigned @>
@d VAX_carriage_control==@= carriage_control @>
@d VAX_io_setmode==@= io$_setmode @>
@d VAX_iom_ctrlcast==@= io$m_ctrlcast @>
@d VAX_immed==@= %immed @>
@d VAX_stdescr==@= %stdescr @>
@d VAX_ref==@= %ref @>
@d VAX_qiow==@= $qiow @>
@d VAX_assign==@= $assign @>
@d VAX_numtim==@= $numtim @>
@d VAX_getsyi==@= $getsyi @>
@d VAX_lib_get_foreign==@= lib$get_foreign @>
@d VAX_disposition==@= disposition @>
@d VAX_delete==@= delete @>
@d VAX_save==@= save @>
@d VAX_varying==@= varying @>
@d VAX_substr==@= substr @>
@d VAX_trnlog==@= $trnlog @>
@d VAX_ss_normal==@= ss$_normal @>

@<Compiler directives@>=
@=[check(none)]@> {no debug overhead, but...}
debug @=[check(all)]@> gubed {turn everything on when debugging}
@z

@x Define the compile-time constant |max_rescan| for command-line processing
@!lit_stk_size=100; {maximum number of literal functions on the stack}
@y
@!lit_stk_size=100; {maximum number of literal functions on the stack}
@!max_cmdline=500; {maximum length of the rescan buffer}
@z

@x
@<Types in the outer block@>=
@y
@<Types in the outer block@>=
@!word_type = [word]-32768..32767;	{16-bit integers}
@z

@x
@!alpha_file=packed file of text_char; {files that contain textual data}
@y
@!alpha_file=text; {files that contain textual data}
@z

@x
@d reset_OK(#)==erstat(#)=0
@d rewrite_OK(#)==erstat(#)=0

@<Procedures and functions for file-system interacting@>=
function erstat(var f:file):integer; extern;	{in the runtime library}
@#@t\2@>
function a_open_in(var f:alpha_file):boolean;	{open a text file for input}
begin reset(f,name_of_file,'/O'); a_open_in:=reset_OK(f);
end;
@#
function a_open_out(var f:alpha_file):boolean;	{open a text file for output}
begin rewrite(f,name_of_file,'/O'); a_open_out:=rewrite_OK(f);
end;
@y
@<Procedures and functions for file-system interacting@>=
function a_open_in(var f:alpha_file):boolean;	{open a text file for input}
begin
open(f,name_of_file,VAX_readonly,VAX_error:=VAX_continue);
if status(f)>0 then a_open_in:=false
else begin
 reset(f,VAX_error:=VAX_continue);
 a_open_in:=status(f)<=0;
 end;
end;
@#
function a_open_out(var f:alpha_file):boolean;	{open a text file for output}
begin
open(f,name_of_file,VAX_new,16383,{VAX\_disposition:=VAX\_delete,}
	VAX_error:=VAX_continue);
if status(f)>0 then a_open_out:=false
else begin
 rewrite(f,VAX_error:=VAX_continue);
 a_open_out:=status(f)<=0;
 end;
end;
@z

@x
pre_define('texinputs:  ',10,file_area_ilk);
s_bst_area := hash_text[pre_def_loc];
pre_define('texbib:     ',7,file_area_ilk);
s_bib_area := hash_text[pre_def_loc];
@y
pre_define('tex$inputs: ',11,file_area_ilk);
s_bst_area := hash_text[pre_def_loc];
pre_define('tex$bib:    ',8,file_area_ilk);
s_bib_area := hash_text[pre_def_loc];
@z

@x
check_cmnd_line := false;			{many systems will change this}
@y
check_cmnd_line := true;			{many systems will change this}
@z

@x And finally, here's the code that handles the command line argument.
@<Process a possible command line@>=
begin
do_nothing;		{the ``default system'' doesn't use the command line}
end
@y
On VAX/VMS, we can make a program runnable by name by defining a foreign
command symbol for it; the command line is then accessible via a call to
\.{lib\$get\_foreign()}.  Since all we need is a single word off the
command line, and since prompting for the input of that word is both a
nuisance, and precludes use of nice utilities like \.{Make}, it seems
simplest to pick up the name from the command line.

The Kellerman and Smith VMS \TeX{} implementation takes this notion a
step further, and adds code to support running the program in native
mode, complete with command line switches and fancy parsing; they have
more ambition than I do just now.

@<Process a possible command line@>=
begin
  get_cmdline;
  if (aux_name_length = file_name_size) then
    sam_you_made_the_file_name_too_long
  else if (aux_name_length = 0) then
    goto aux_not_found
end
@
@<Procedures and functions for all file I/O, error messages, and such@>=
function VAX_lib_get_foreign(VAX_stdescr s :
		packed array [a..b : integer] of char;
	%immed p2 : integer;
	var p3 : word_type) : integer;
	fortran;
@#
procedure get_cmdline;
label exit;
var
	cmdline : packed array [1..max_cmdline] of char;
	cmdlength : word_type;
	i : integer;
@#
begin
	aux_name_length := 0;
	if not odd (VAX_lib_get_foreign(cmdline,0,cmdlength)) then
	begin
		print_ln('Cannot get command line; use "bibtex file"');
		return
	end;
@#
	i:=1;
	while (i<=cmdlength) and (cmdline[i]=' ') do incr(i); {skip spaces}@/
	if i>cmdlength then return; {there was no argument}
@#
	while (cmdline[i]>' ') do	{copy the argument into |name_of_file|}
	begin
	    if (aux_name_length = file_name_size) then
		return;
	    incr(aux_name_length);
	    name_of_file[aux_name_length] := cmdline[i];
	    incr(i)
	end;
exit:
end;
@
@z

@x
This section should be replaced, if necessary, by changes to the program
that are necessary to make \BibTeX\ work at a particular installation.
It is usually best to design your change file so that all changes to
previous sections preserve the section numbering; then everybody's version
will be consistent with the printed program. More extensive changes,
which introduce new sections, can be inserted here; then only the index
itself will get a new section number.
@y
Here are the remaining changes to the program
that are necessary to make \.{TeX} work on Vax/VMS.

@z