4th(1) - f30

14th(1)                      General Commands Manual                     4th(1)
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NAME

6       4th  -  a  portable  Forth  compiler  supporting a (modified) subset of
7       ANS-Forth
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SYNTAX

10       4th [options] [file] [file | argument .. argument]
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12       4thx [file] [argument .. argument]
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DESCRIPTION

15       4th is a menudriven bytecode  compiler,  virtual  machine,  decompiler,
16       line  editor,  RPN  calculator  and  C-source generator rolled into one
17       small program. You can use it to  create  portable  bytecode  programs,
18       standalone  executables  or  as  a  scripting  language or a Forth-to-C
19       translator. For details read the manual.
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OPTIONS

22       m      enter interactive mode
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24       e      edit a 4tH screenfile
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26       c      load a sourcefile (.4th) and compile it
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28       l      load an objectfile (.hx)
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30       d      decompile a 4tH program
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32       g      generate a C sourcefile (default: out.c)
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34       s      save a 4tH program (default: out.hx)
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36       x      execute a 4tH program
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38       v      enter verbose mode
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40       q      suppress copyright message
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EDITOR

43       n D    Delete line n but hold it in PAD. Line 15 becomes  free  as  all
44              statements move up 1 line.
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46       n E    Erase line n with blanks.
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48       n I    Insert  the  text  from PAD at line n, moving the old line n and
49              following lines down. Line 15 is lost.
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51       n H    Hold line n at PAD (used by system more often than by user).
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53       n R    Replace line n with the text in PAD.
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55       n S    Spread at line n. Line n and following lines move down  1  line.
56              Line n becomes blank. Line 15 is lost.
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58       n T    Display line n and copy it to PAD.
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60       n P text
61              Put 'text' at line n, overwriting its previous contents.
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63       n LIST List  screen n and select it for editing: if screen n is not the
64              current screen, it will request to load from memory.
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66       n CLEAR
67              Clear screen n with blanks and select it for editing.
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69       n INSERT
70              Insert screen n. The current screen n and all screens  following
71              it  are moved down. The last screen is lost. Clear screen n with
72              blanks and select it for editing. FLUSH Used at the  end  of  an
73              editing session to save the current screen to memory.
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75       UNDO   Used  to  reload  the  current  screen  again,  thus undoing all
76              changes since the last  flush  (triggered  by  CLEAR,  FLUSH  or
77              LIST).
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79       FLUSH  Write updated screen to memory.
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81       L      List  the  current screen. The cursor line is relisted after the
82              screen listing to show the cursor position.
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84       n M    Move the cursor by n characters and the cursor line.  The  posi‐
85              tion of the cursor on its line is shown by a ^ (caret).
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87       n W    Wipe n characters to the left of the cursor.
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89       TOP    Position the cursor at the start of the screen.
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91       B      Used  after  F  to  back up the cursor by the length of the most
92              recent text.
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94       C text Copy in text to the cursor line at the cursor position.
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96       F text Search forward from the current  cursor  position  until  string
97              'text' is found. The cursor is left at the end of the string and
98              the cursor line printed. If the string is  not  found  an  error
99              message  is  given and the cursor repositioned to the top of the
100              screen.
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102       N      Find the next occurrence of the string found by an F command
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104       TILL text
105              Delete on the cursor line from the cursor till the end of string
106              text.
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108       X text Find and delete the next occurrence of the string 'text'.
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110       EXPORT file
111              Saves  the  current contents of all screens to text-file 'file'.
112              No flushing is done.
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114       WRITE  Saves the current contents of all screens to the block-file.  No
115              flushing is done.
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117       WQ     Flushes the current screen and saves the current contents of all
118              screens to the block-file.
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120       Q      Quits the editor without saving.
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FILES

123       *.4th; text files containing 4tH source  (script)
124       *.scr; block files containing 4tH source (script)
125       *.hx; Hcode eXecutables (bytecode)
126       *.c; C source files
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ENVIRONMENT VARIABLES

129       DIR4TH If non-null the full pathname (including the trailing slash) for
130              the 4tH root directory. Used only by the compiler.
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EXAMPLES

133       To compile a 4tH program and save the object code:
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135       4th csv source.4th [object.hx]
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137       To compile a 4tH program and execute it:
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139       4th cx source.4th
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141       To decompile object code:
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143       4th ld object.hx
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145       To convert object code to C source:
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147       4th lg object.hx [source.c]
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149       To load and execute object code:
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151       4th lx object.hx [arguments]
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153       To load and execute object code without arguments:
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155       4th object.hx
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157       To edit a 4tH screenfile:
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159       4th e source.scr
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161       To enter interactive mode:
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163       4th m source.scr
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165       To enter interactive mode (without a screenfile):
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167       4th
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AUTHORS

170       4tH was written by Hans Bezemer <the.beez.speaks@gmail.com>
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