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Diffstat (limited to 'systems/unix/tex-fpc/mf.ch')
| -rw-r--r-- | systems/unix/tex-fpc/mf.ch | 845 |
1 files changed, 845 insertions, 0 deletions
diff --git a/systems/unix/tex-fpc/mf.ch b/systems/unix/tex-fpc/mf.ch new file mode 100644 index 0000000000..0b697ec3da --- /dev/null +++ b/systems/unix/tex-fpc/mf.ch @@ -0,0 +1,845 @@ +% This is a change file of Metafont for FPC, Wolfgang Helbig, Nov. 2007 +[0] to print changed sections only +@x +\def\gglob{20, 26} % this should be the next two sections of "<Global...>" +@y +\def\gglob{20, 26} % this should be the next two sections of "<Global...>" +\input webmac-fpc +\emergencystretch 0.5in % avoid overfull boxes + +\let\maybe=\iftrue % print changed modules only. + +\def\name{\MF} + +\N0\*. \[0] About \namefpc. + +This is an adaption of Donald~E. Knuth's \MF, version 2.7182815 +from January 2014, to Free~Pascal (FPC) and Unix. + +The features added include treating the command line as the first +input line and invoking a system editor, in this case \.{vi}, to +let the user correct the input file. +On exit, \namefpc\ passes its `history' to the operating system. + +The changes needed to make \namefpc\ compile and run to my satisfaction +are very similar to those applied to \TeXfpc. Look in tex.tex for +a thorough description of adaptions to Unix, FPC, and my taste. + +\hint + +Comments and questions are welcome! + +\bigskip +\address +\fi +@z + +[2] Change the banner line +@x +@d banner=='This is METAFONT, Version 2.7182818' {printed when \MF\ starts} +@y +@d banner=='This is METAFONT-FPC, 2nd ed.' {printed when \MF\ starts} +@z + +[4] terminal output and input +@x +@^system dependencies@> + +@d mtype==t@&y@&p@&e {this is a \.{WEB} coding trick:} +@y +@^system dependencies@> + +@d term_in==i@&n@&p@&u@&t +@d term_out==o@&u@&t@&p@&u@&t +@d mtype==t@&y@&p@&e {this is a \.{WEB} coding trick:} +@z + +[4] terminal output and input +@x +program MF; {all file names are defined dynamically} +@y +program MF(@!term_in,@!term_out); +{all other file names are defined dynamically} +@z + +[4] forward declaration for signal handler +@x +procedure initialize; {this procedure gets things started properly} +@y +procedure catch_signal(i: integer); interrupt; forward; +procedure initialize; {this procedure gets things started properly} +@z + +Since @x, @y, and @z only define a change block when they begin a +line, you deactivate a block by indenting it (shift right) and +activate it by unindenting it (shift left). With vi set the +cursor to the @x line and enter >} or <} to (un)indent a paragraph. + +[7] shift left to turn debugging on, right to turn it off + @x debug + @d debug==@{ {change this to `$\\{debug}\equiv\null$' when debugging} + @d gubed==@t@>@} {change this to `$\\{gubed}\equiv\null$' when debugging} + @y + @d debug== {change this to `$\\{debug}\equiv\.{@@\{}$' when not debugging} + @d gubed== {change this to `$\\{gubed}\equiv\.{@@\}}$' when not debugging} + @z + +[7] shift left to turn on statistics, shift rigth to turn off statistics + @x stat + @d stat==@{ {change this to `$\\{stat}\equiv\null$' when gathering + usage statistics} + @d tats==@t@>@} {change this to `$\\{tats}\equiv\null$' when gathering + usage statistics} + @y + @d stat== {change this to `$\\{stat}\equiv\.{@@\{}$' to turn off statistics} + @d tats== {change this to `$\\{tats}\equiv\.{@@\}}$' to turn off statistics} + @z + + [8] shift left to build MF and right it to build INIMF. + @x inimf + @d init== {change this to `$\\{init}\equiv\.{@@\{}$' in the production version} + @d tini== {change this to `$\\{tini}\equiv\.{@@\}}$' in the production version} + @y + @d init==@{ + @d tini==@} + @z + +[9] compiler directives, turn off I/O checking. +@x +@{@&$C-,A+,D-@} {no range check, catch arithmetic overflow, no debug overhead} +@!debug @{@&$C+,D+@}@+ gubed {but turn everything on when debugging} +@y +@{$MODE@,ISO@} {turn on mode ISO} +@{$Q+@} {turn on overflow checking} +@{$R+@} {turn on range checking} +@!debug @{Q+@}@,@{R+@}@+ gubed {turn checks off when debugging} +@z + +[10] default case branch +@x +@d othercases == others: {default for cases not listed explicitly} +@y +@d othercases == @+ else {default for cases not listed explicitly} +@z + +Shift left all `trap' blocks to prepare for TRAP. +Shift right all `part' blocks to prepare for TRAP. +[11] +@x part +@!mem_max=30000; {greatest index in \MF's internal |mem| array; +@y +@!mem_max=35000; {increased for ibycus4, + greatest index in \MF's internal |mem| array; +@z + +[11] +@x part +@!max_strings=2000; {maximum number of strings; must not exceed |max_halfword|} +@y +@!max_strings=6000; {maximum number of strings; increased for ibycus4} +@z + +@x part +@!pool_size=32000; {maximum number of characters in strings, including all +@y +@!pool_size=60000; {increased for ibycus4, + maximum number of characters in strings, including all +@z + +[11] + @x trap + @!mem_max=30000; {greatest index in \MF's internal |mem| array; + @y + @!mem_max=3000; {greatest index in \MF's internal |mem| array; + @z + +[11] + @x trap + @!error_line=72; {width of context lines on terminal error messages} + @!half_error_line=42; {width of first lines of contexts in terminal + error messages; should be between 30 and |error_line-15|} + @!max_print_line=79; {width of longest text lines output; should be at least 60} + @!screen_width=768; {number of pixels in each row of screen display} + @!screen_depth=1024; {number of pixels in each column of screen display} + @y + @!error_line=64; {width of context lines on terminal error messages} + @!half_error_line=32; {width of first lines of contexts in terminal + error messages; should be between 30 and |error_line-15|} + @!max_print_line=72; {width of longest text lines output; should be at least 60} + @!screen_width=100; {number of pixels in each row of screen display} + @!screen_depth=200; {number of pixels in each column of screen display} + @z + +[11] + @x trap + @!gf_buf_size=800; {size of the output buffer, must be a multiple of 8} + @y + @!gf_buf_size=8; {size of the output buffer, must be a multiple of 8} + @z + +[11] location of pool file +@x +@!pool_name='MFbases:MF.POOL '; +@y +@!pool_name='MFbases/mf.pool'; +@z + + +[12] +@x part +@d mem_top==30000 {largest index in the |mem| array dumped by \.{INIMF}; +@y +@d mem_top==35000 {largest index in the |mem| array dumped by \.{INIMF}; +@z + +[12] + @x trap + @d mem_top==30000 {largest index in the |mem| array dumped by \.{INIMF}; + @y + @d mem_top==3000 {largest index in the |mem| array dumped by \.{INIMF}; + @z + +[12] Silvio levy' greek fonts need more opened input files. +@x part +@d max_in_open=6 {maximum number of input files and error insertions that +@y +@d max_in_open=10 {maximum number of input files and error insertions that +@z + +[22] accept tab and formfeed +@x +for i:=0 to @'37 do xchr[i]:=' '; +@y +for i:=0 to @'37 do xchr[i]:=' '; +xchr[@'11] := chr(@'11); {accept horizontal tab} +xchr[@'14] := chr(@'14); {accept form feed} +@z + +[24] the type of text_files is text in ISO Pascal +@x +@!eight_bits=0..255; {unsigned one-byte quantity} +@!alpha_file=packed file of text_char; {files that contain textual data} +@y +@!eight_bits=0..255; {unsigned one-byte quantity} +@!alpha_file=t@&e@&x@&t; {coding trick is needed since |text| is a macro} +@z + +[26] dynamic io +@x +@d reset_OK(#)==erstat(#)=0 +@d rewrite_OK(#)==erstat(#)=0 +@y +@d fpc_io_result==i@&o@&r@&e@&s@&u@&l@&t +@d fpc_assign==a@&s@&s@&i@&g@&n +@d reset_OK(#)==fpc_io_result=0 +@d rewrite_OK(#)==fpc_io_result=0 +@d clear_io_result==@+if fpc_io_result=0 then do_nothing +@z + +[26] opening for in- and output for all three file types +alpha in +@x +@p 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); +@y +@p @{@&$I-@} {turn off I/O checking} +@# +function a_open_in(var @!f:alpha_file):boolean; + {open a text file for input} +begin clear_io_result; fpc_assign(f,name_of_file);reset(f); +a_open_in:=reset_OK(f); +@z + +[26] +alpha out +@x +begin rewrite(f,name_of_file,'/O'); a_open_out:=rewrite_OK(f); +@y +begin clear_io_result; fpc_assign(f,name_of_file); rewrite(f); +a_open_out:=rewrite_OK(f); +@z + +[26] byte out +@x +begin rewrite(f,name_of_file,'/O'); b_open_out:=rewrite_OK(f); +@y +begin clear_io_result; fpc_assign(f,name_of_file); rewrite(f); +b_open_out:=rewrite_OK(f); +@z + +[26] word in +@x +begin reset(f,name_of_file,'/O'); w_open_in:=reset_OK(f); +@y +begin clear_io_result; fpc_assign(f,name_of_file); reset(f); +w_open_in:=reset_OK(f); +@z + +[26] word out +@x +begin rewrite(f,name_of_file,'/O'); w_open_out:=rewrite_OK(f); +end; +@y +begin clear_io_result; fpc_assign(f,name_of_file); rewrite(f); +w_open_out:=rewrite_OK(f); +end; +@# +@{@&$I+@} {turn on I/O checking} +@z + +[30] bypass_eoln +@x +begin if bypass_eoln then if not eof(f) then get(f); +@y +begin +@z + +[30] bypass_eoln +@x + last:=last_nonblank; input_ln:=true; + end; +@y + last:=last_nonblank; input_ln:=true; + read_ln(f); + end; +@z + +[31] term_in and term_out are the standard pascal files +@x +is considered an output file the file variable is |term_out|. +@^system dependencies@> + +@<Glob...@>= +@!term_in:alpha_file; {the terminal as an input file} +@!term_out:alpha_file; {the terminal as an output file} +@y +is considered an output file the file variable is |term_out|. +The file |term_in| is declared as \\{input} and |term_out| as +\\{output} in the program header. +@^system dependencies@> +@z + +[32] +@x +@d t_open_in==reset(term_in,'TTY:','/O/I') {open the terminal for text input} +@d t_open_out==rewrite(term_out,'TTY:','/O') + {open the terminal for text output} +@y +@d t_open_in==do_nothing {open the terminal for text input} +@d t_open_out==do_nothing {open the terminal for text output} +@z + +[33] +@x +@d update_terminal == break(term_out) {empty the terminal output buffer} +@d clear_terminal == break_in(term_in,true) {clear the terminal input buffer} +@y +@d update_terminal == do_nothing {empty the terminal output buffer} +@d clear_terminal == do_nothing {clear the terminal input buffer} +@z + +[35] command line +@x +@d loc==cur_input.loc_field {location of first unread character in |buffer|} +@y +@d loc==cur_input.loc_field {location of first unread character in |buffer|} +@d fpc_string == s@&h@&o@&r@&t@&s@&t@&r@&i@&n@&g +@d fpc_length==l @& e @& n @& g @& t @& h +@d fpc_param_count==p @& a @& r @& a @& m @& c @& o @& u @& n @& t +@d fpc_param_str==p @& a @& r @& a @& m @&s @& t @& r + {FPC function returning the length of a |fpc_string|} +@d fpc_int_to_str == i @& n @& t @& t @& o @& s @& t @& r + +@p procedure input_command_ln; {get the command line in |buffer|} +var argc: integer; {argument counter} + arg: fpc_string; {argument} + cc: integer; {character counter in argument} +begin last := first; argc := 1; +while argc <= fpc_param_count do + begin cc := 1; arg := fpc_param_str(argc); incr(argc); + while cc <= fpc_length(arg) do + begin + if last+1>=buf_size then + @<Report overflow of the input buffer, and abort@>; + buffer[last] := xord[arg[cc]]; incr(last); incr(cc); + end; + if (argc <= fpc_param_count) then begin + buffer[last] := " "; incr(last); + end; + end; +end; +@z + +[36] command line +@x +@p function init_terminal:boolean; {gets the terminal input started} +label exit; +begin t_open_in; +loop@+begin wake_up_terminal; write(term_out,'**'); update_terminal; +@y +@p function init_terminal:boolean; {gets the terminal input started} +label exit; +begin t_open_in; input_command_ln; +loc := first; +if loc<last then + begin init_terminal:=true; return; {first line is the command line} + end; +loop@+begin wake_up_terminal; write(term_out,'**'); update_terminal; +@z + +[36] For Unix, End of file on the terminal is not remarkable +@x + write(term_out,'! End of file on the terminal... why?'); +@.End of file on the terminal@> +@y +@z + +[36] control D +@x + write_ln(term_out,'Please type the name of your input file.'); +@y + write_ln(term_out,'Please type the name of your input file or Control-D.'); +@z + +[51] leave pool file open +@x +@ @d bad_pool(#)==begin wake_up_terminal; write_ln(term_out,#); + a_close(pool_file); get_strings_started:=false; return; + end +@y +@ @d bad_pool(#)==begin wake_up_terminal; write_ln(term_out,#); + get_strings_started:=false; return; + end +@z + +[51] lower case name of mf.pool +@x +else bad_pool('! I can''t read MF.POOL.') +@y +else bad_pool('! I can''t read mf.pool.') +@z + +[74] start editor +@x +@!use_err_help:boolean; {should the |err_help| string be shown?} +@y +@!use_err_help:boolean; {should the |err_help| string be shown?} +@!start_edit: boolean; {start \.{vi}?} +@z + +[75] initial value for edit argument +@x +help_ptr:=0; use_err_help:=false; err_help:=0; +@y +help_ptr:=0; use_err_help:=false; err_help:=0; +start_edit := false; { don't start \.{vi}} +@z + +[79] set edit_cmd +@x + begin print_nl("You want to edit file "); +@.You want to edit file x@> + slow_print(input_stack[file_ptr].name_field); + print(" at line "); print_int(line);@/ + interaction:=scroll_mode; jump_out; + end; +@y + begin {save values to be passed to the system editor} + start_edit := true; + interaction:=scroll_mode; jump_out; + end; +@z + +[81] extra space on log file and terminate last terminal line +@x +"Q":begin print("batchmode"); decr(selector); + end; +@y +"Q":begin print("batchmode"); + end; +@z + +[81] continued +@x +print("..."); print_ln; update_terminal; return; +@y +print("..."); print_ln; update_terminal; +if c="Q" then decr(selector); return; +@z + +[194] date and time +@x +@p procedure fix_date_and_time; +begin internal[time]:=12*60*unity; {minutes since midnight} +internal[day]:=4*unity; {fourth day of the month} +internal[month]:=7*unity; {seventh month of the year} +internal[year]:=1776*unity; {Anno Domini} +end; +@y +@p procedure fix_date_and_time; +var yy,mm,dd: word; + hh,ss,ms: word; +begin +decodedate(now,yy,mm,dd); {current date} +internal[day] := dd*unity; +internal[month] := mm*unity; +internal[year] := yy*unity;@/ +decodetime(now,hh,mm,ss,ms); {current time} +internal[time] := (hh*60+mm)*unity; {minutes since midnight} +end; +@z + +[199] character class for tab and lf +@x +for k:=127 to 255 do char_class[k]:=invalid_class; +@y +for k:=127 to 255 do char_class[k]:=invalid_class; +char_class[@'11] := space_class; +char_class[@'14] := space_class; +@z + +[326] +@x +no rows), we have |n_rover(h)=h|, and |n_pos(h)| is irrelevant. +@y +no rows), we have |n_rover(h)=h|, and |n_pos(h)| is irrelevant. + +The definition of |valid_range| was changed because the Free Pascal +Compiler cannot compile expressions like |abs(a+b-4096)| when |a| +and |b| are |half_words|. It does compile however |abs(int(a+b) - +int(4096))|, and |abs(int(a+b-4096))| will throw an overflow exception. +@z + +[326] +@x +@d valid_range(#)==(abs(#-4096)<4096) {is |#| strictly between 0 and 8192?} +@y +@d valid_range(#)==(abs(int(#)-int(4096))<4096) {is |#| strictly between 0 and 8192?} +@z + + [536] undo Knuth's change from mf-2008 to mf-2012, to explain the + diffs of pointer values in the trap.logs. + @x + done1: if (link(p)<>null) then free_node(link(p),knot_node_size); + link(p):=s; beta:=-y_coord(h); + @y + done1: link(p):=s; beta:=-y_coord(h); + @z + +[564] + @x trap + begin init_screen:=false; + @y + begin init_screen:=true; + @z + +[679] spurious empty line on terminal + @x chatty + print_ln; first:=start; + prompt_input("*"); {input on-line into |buffer|} + @y + @.Please type...@> + print_nl(""); + first:=start; {avoid empty lines on terminal and log file} + prompt_input("*"); {input on-line into |buffer|} + @z + +[769] Path separator in Unix +@x +@d MF_area=="MFinputs:" +@y +@d MF_area=="MFinputs/" +@z + +[771] +@x +else begin if (c=">")or(c=":") then +@y +else begin if c="/" then +@z + +[774] +@x +@d append_to_name(#)==begin c:=#; incr(k); +@y +@d fpc_set_length==s@&e@&t@&l@&e@&n@&g@&t@&h +@d append_to_name(#)==begin c:=#; incr(k); +@z + +[774] +@x +@!j:pool_pointer; {index into |str_pool|} +@y +@!j:pool_pointer; {index into |str_pool|} +rbs: fpc_string; +@z + +[774] +@x +for k:=name_length+1 to file_name_size do name_of_file[k]:=' '; +@y +rbs := name_of_file; +fpc_set_length(rbs, name_length); +name_of_file := rbs; +@z + +[776] +@x +MF_base_default:='MFbases:plain.base'; +@y +MF_base_default:='MFbases/plain.base'; +@z + +[778] +@x +@!j:integer; {index into |buffer| or |MF_base_default|} +@y +@!j:integer; {index into |buffer| or |MF_base_default|} +rbs: fpc_string; +@z + +[778] +@x +for k:=name_length+1 to file_name_size do name_of_file[k]:=' '; +@y +rbs := name_of_file; +fpc_set_length(rbs, name_length); +name_of_file := rbs; +@z + +[786] +@x spaeter! +print_nl("Please type another "); print(s); +@y +print_nl("Please type another "); print(s); print(" or Control-D"); +@z + +[793] name might be needed to be passed to vi +@x +if name=str_ptr-1 then {we can conserve string pool space now} + begin flush_string(name); name:=cur_name; + end; +@y +@^Editor@> +@z + + + [1023] avoid blank line on terminal after mode command + @x chatty + mode_command: begin print_ln; interaction:=cur_mod; + @y + mode_command: begin print_nl(""); interaction:=cur_mod; + @z + +[1154] blockwrite for gf_buf +@x +output an array of words with one system call. +@y +output an array of words with one system call. + +@d fpc_blockwrite == b @& l @& o @& c @& k @& w @& r @& i @& t @& e +@z + +@x +begin for k:=a to b do write(gf_file,gf_buf[k]); +@y +begin fpc_blockwrite(gf_file,gf_buf[a],b-a+1); +@z + +[1199] +@x +undump_int(x);@+if (x<>69069)or eof(base_file) then goto off_base +@y +undump_int(x);@+if (x<>69069) then goto off_base +@z + +[1204] +@x +@p begin @!{|start_here|} +@y +@d fpc_halt == h@&a@&l@&t + +@p begin @!{|start_here|} +@z + +[1204] start editor and pass history +@x +final_end: ready_already:=0; +@y +final_end: +if start_edit then exec_editor; {user typed `\.{E}'} +fpc_halt(history); + {pass |history| as the exit value to the system} +@z + +[1205] terminate last line +@x + slow_print(log_name); print_char("."); +@y + slow_print(log_name); print_char("."); print_ln; +@z + +[1212] return if eof +@x + read(term_in,m); +@y + if eof(term_in) then return; + {don't try to read past end of file} + read(term_in,m); +@z + +[1212] return if eof +@x + else begin read(term_in,n); +@y + else begin if eof(term_in) then return; + {don't try to read past end of file} + read(term_in,n); +@z + +[1213] return eof +@x +13: begin read(term_in,l); print_cmd_mod(n,l); +@y +13: begin if eof(term_in) then return; + {don't try to read past end of file} +read(term_in,l); print_cmd_mod(n,l); +@z + +[1214 and modules added for METAFONT-FPC] +@x +itself will get a new section number. +@^system dependencies@> +@y +itself will get a new section number. +@^system dependencies@> +@^fpc Pascal@> + +@d edit_file == input_stack[file_ptr].name_field +@d fpc_fp_exec_vp == fp_exec_vp +@d fpc_pchar == pchar +@d vi==@{ {change this to `$\\{vi}\equiv\null$' when you think \.{vi} +is the system editor} +@d iv==@t@>@} {change this to `$\\{iv}\equiv\null$' when you think \.{vi} +is the sytem editor} +@f vi == begin +@f iv == end +@d ed== {change this to `$\\{ed}\equiv\.{@@\{}$' when you think \.{vi} +is the system editor} +@d de== {change this to `$\\{de}\equiv\.{@@\}}$' when you think \.{vi} +is the system editor} +@f ed == begin +@f de == end + +@<Last-minute...@>= +procedure exec_editor; +const arg_size = 100; {maximal size of each of the arguments} + vi editor = 'vi'; {name of the binary to be started} + iv + @# + ed editor = 'ed'; {name of the binary to be started} + de + @# + editor_length = 2; {length of the name} +var i, l: integer; {index into args} + j: pool_pointer; {index into |str_pool|} + s: str_number; {string to hold line number} + sel: integer; { save selector } + editor_arg, line_arg, file_arg : array[1..arg_size] of char; { arguments } + argv: array [0..3] of fpc_pchar; { vector of arguments } +begin + l := editor_length; + for j := 1 to l do editor_arg := editor[j]; + editor_arg[l+1] := chr(0); + + sel := selector; + selector := new_string; + print_int(line); + s := make_string; + @# + vi + line_arg[1] := '+'; + j := str_start[s]; + l := length(s)+1; + for i := 2 to l do begin line_arg[i] := xchr[str_pool[j]]; incr(j) end; + line_arg := chr(0); + iv + @# + ed + selector := term_only; + write('You want to edit at line '); print(s); print_ln; + de + @# + selector := sel; + j := str_start[edit_file]; + l := length(edit_file); + if l+1 > arg_size then begin + write_ln('File name longer than 100 bytes! Nice try!'); + halt(100); + end; + for i := 1 to l do + begin file_arg[i] := xchr[str_pool[j]]; incr(j) + end; + file_arg[l+1] := chr(0); + argv[0] := @@editor_arg; + vi + argv[1] := @@line_arg; + argv[2] := @@file_arg; + argv[3] := nil; + iv + @# + ed + argv[1] := @@file_arg; + argv[2] := nil; + de + @# + fpc_fp_exec_vp(editor, argv); + write_ln('Sorry, executing the editor failed.'); +end; +@ +A signal handler is a procedure that takes one |integer| parameter. +The procedure |fpc_fp_signal| takes two parameter, an integer and +a signal handler. The integer is the number of the signal. Whenever +the program receives a signal with the designated number, the signal handler +gets invoked. + +The integer |SIGINT| is the number of the interrupt signal. The +system sends an interrupt signal to the program, whenever the user +types \.{\^C}. + +The function |fpc_fp_get_errno| returns an integer that is not zero, +whenever something went wrong. + +The identifier |fpc_signal_handler| denotes the |type| of a +pointer to a signal handler. Since this is foreign to ISO~Pascal, +we use the type cast to |fpc_signal_handler| as a kludge. + +@^FPC Pascal@> +@^system dependencies@> + +@d fpc_signal_handler == s@&i@&g@&n@&a@&l@&h@&a@&n@&d@&l@&e@&r +@d fpc_fp_signal == f@&p@&s@&i@&g@&n@&a@&l +@d fpc_fp_get_errno ==f@&p@&g@&e@&t@&e@&r@&r@&n@&o + +@<Set initial values ...@>+= + +fpc_fp_signal(SIGINT, fpc_signal_handler(catch_signal)); +if fpc_fp_get_errno <> 0 then + write_ln('Could not install signal handler:', fpc_fp_get_errno); + +@ The signal handler has the so called modifier |interrupt|. +Modifiers are an extension of FPC Pascal. This one makes the compiler +generate the code suitable for a signal handler, which must not +return to the caller but to the instruction where the program was +interrupted. + +@^FPC Pascal@> +@^system dependencies@> + +@<Error handling ...@>+= +procedure catch_signal; interrupt; +begin + interrupt := i; +end; +@z |