Linux builds of µEforth are no longer published as this isn't really ideal for Linux anyway.
Instead build as follows:
sudo apt install ninja-build git clone https://github.com/flagxor/ueforth cd ueforth ./configure.py ninja
http://github.com/flagxor/ueforth - Complete Unprocessed Source Code
As null terminated strings are used throughout C interfaces, their use is supported in Forth by way of several non-standard words with the convention of using Z/z to refer to such strings in names and stack comments.
Z" ( "string" -- z ) Creates a null terminated string on the heap Z>S ( z -- a n ) Convert a null terminated string to a counted string S>Z ( a n -- z ) Conver a counted string string to null terminated (copies string to heap)
Raw strings are provided better support using a string for the duration of the current command, without consuming heap memory.
R" ( "string" -- a n ) Creates a temporary counted string R| ( string| -- a n ) Creates a temporary counted string ending with |
DUMP ( a n -- ) Dump a memory region SEE ( "name" -- ) Attempt to decompile a word VARIABLE ECHO -- Determines if commands are echoed REMAINING ( -- n ) Bytes remaining in Forth heap. DUMP-FILE ( data data# fn fn# -- ) Write contents of a file throws on error.
uEForth uses a hybrid of Forth-79 and Forth-83 style vocabularies.
By default vocabularies chain to the vocabulary in which they were defined,
as in Forth-79. However, like Forth-83, ALSO
can be used to add vocabularies to a vocabulary stack of which
CONTEXT @ is the first item.
The word ONLY clears the vocabulary stack, but as there is
no separate ONLY vocabulary, it also sets CONTEXT
to the FORTH vocabulary.
The word SEALED modifies the most recently defined vocabulary
such that it does not chain. Note, this must be done before words are added to it.
VOCABULARY ( "name" ) Create a vocabulary with the current vocabulary as parent
FORTH ( -- ) Make the FORTH vocabulary the context vocabulary
DEFINITIONS ( -- ) Make the context vocabulary the current vocabulary
VLIST ( -- ) List the words in the context vocabulary (not chains)
WORDS ( -- ) List the words in the context vocabulary (including chains)
TRANSFER ( "name" ) Move a word from its current dictionary to the current vocabulary
Useful for "hiding" built-in words
TRANSFER{ ..words.. }TRANSFER ( -- ) Transfer multiple words to the current vocabulary
ALSO ( -- ) Duplicate the vocabulary at the top of the vocabulary stack
PREVIOUS ( -- ) Drop the vocabulary at the top of the vocabulary stack
ONLY ( -- ) Reset context stack to one item, the FORTH dictionary
Non-standard, as there's no distinct ONLY vocabulary
ORDER ( -- ) Print the vocabulary search order
SEALED ( -- ) Alter the last vocabulary defined so it doesn't chain
[IF], [ELSE], and [THEN] can be used
to selectively compile. Used in tandem with DEFINED? they can
be used to handle the absence of modules gracefully.
Nesting is supported.
DEFINED? ( "name" -- xt|0 ) Check if a word exists (works at compile time too). [IF] ( f -- ) Conditionally interpret the text the follows. [ELSE] ( -- ) Interpret time ELSE. [THEN] ( -- ) Interpret time THEN.
Requires v7.0.6.5+
Single precision floating-point support is available as a work in progress. While initially left out in the name of minimalism, hardware support for floating-point argues some advantages to limited support.
Floating point is kept on a separate stack.
NOTE: Tasks currently don't correctly support floating point. A single floating point stack is shared by all tasks.
FLOAT OPCODES ------------- DOFLIT ( --- ) Puts a float from the next cell onto float stack. FP@ ( -- a ) FP! ( a -- ) SF@ ( a -- r ) Single precision load SF! ( r a -- ) Single precision store FDUP ( r -- r r ) FNIP ( ra rb -- rb ) FDROP ( r -- ) FOVER ( ra rb -- ra rb ra ) FSWAP ( ra rb -- rb ra ) F0< ( r -- f ) F0= ( r -- f ) F+ ( r r -- r ) F- ( r r -- r ) F* ( r r -- r ) F/ ( r r -- r ) 1/F ( r -- r ) S>F ( n -- r ) F>S ( r -- n ) HIGH LEVEL ---------- F= ( r r -- f ) F< ( r r -- f ) F> ( r r -- f ) F<= ( r r -- f ) F>= ( r r -- f ) F<> ( r r -- f ) SFLOAT ( -- 4 ) SFLOATS ( n -- n*4 ) SFLOAT+ ( a -- a+4 ) SF, ( r -- ) AFLITERAL ( r -- ) FLITERAL ( r -- ) IMMEDIATE FCONSTANT ( r "name" ) FVARIABLE ( "name" ) PI ( -- r ) FSQRT ( r r -- r ) F.S ( -- ) Print float stack.
Locals allow named word local parameters and values.
Syntax:
{ local1 local2 .. -- comment }
or
{ local1 local2 .. }
Locals are ordered to match the stack, examples:
: 2OVER { a b c d } a b c d a b ;
: MAX { a b -- biggest } a b < IF b ELSE a THEN ;
( Equivalent with DO and FOR )
: POW2 { n } 1 { s } n FOR AFT s 2* to s THEN NEXT s ;
: POW2 { n } 1 { s } n 0 DO s 2* to s LOOP s ;
Capabilities and limitations:
>R R>) - NOT OK(LOCAL) is also supported.Requires v7.0.7.3+ -- ONLY Posix + ESP32
cp ( "src" "dst" -- ) Copy "src" file to "dst". mv ( "src" "dst" -- ) Rename "src" file to "dst". rm ( "path" -- ) Remove "path" file. touch ( "path" -- ) Create "path" file if it doesn't exist. cat ( "path" -- ) Print contents of "path" file. ls ( "path" -- ) List files or directories in "path".
Requires v7.0.7.3+ -- ONLY Posix
cd ( "path" -- ) Change director to "path". mkdir ( "path" -- ) Create directory "path". rmdir ( "path" -- ) Remove directory "path". pwd ( -- ) Print current directory.
Requires v7.0.7.2+
VISUAL EDIT ( "path" --) Enters a visual editor opening file "path".
NOTE: On ESP32 requires connection over an ANSI serial terminal like Putty.
LIMITATIONS: Terminal doesn't know screen dimensions
and is very redraw inefficient.
Keys:
Ctrl-S -- Save now.
Ctrl-X / Ctrl-Q -- Quit, asking Y/N to save.
Ctrl-L -- Redraw the screen.
Backspace -- Delete a character backwards.
Arrow Keys -- Movement.
PgUp/PgDn -- Scroll up/down a page.
USE ( "name" -- ) Use "name" as the blockfile, e.g. USE /spiffs/foo OPEN-BLOCKS ( a n -- ) Open a file as the block file LOAD ( n -- ) Evaluate a block THRU ( a b -- ) Load blocks a thru b LIST ( n -- ) List a block BLOCK ( n -- a ) Get a 1024 byte block BUFFER ( n -- a ) Get a 1024 byte block without regard to old contents UPDATE ( -- ) Mark the last block modified FLUSH ( -- ) Save and empty all buffers EMPTY-BUFFERS ( -- ) Empty all buffers SAVE-BUFFERS ( -- ) Save all buffers SCR ( -- a ) Pointer to last listed block
EDITOR vocabulary.
Note the block editor places newlines in the 63rd column of each line
to make the block file readable in a text editor.
WIPE ( -- ) Blank out the current block L ( -- ) List the current block D ( n -- ) Delete a line in the current block E ( n -- ) Clear a line in the current block R ( n "text" -- ) Replace a line in the current block A ( n "text" -- ) Add (insert) a line in the current block P ( -- ) Move to the previous block N ( -- ) Move to the next block
Requires v7.0.7.2+ for UDP
These words are available inside thesockets vocabulary.
socket ( domain type protocol -- sock/err ) setsockopt ( sock level optname optval optlen -- 0/err ) bind ( sock addr addrlen -- 0/err ) listen ( sock connections -- 0/err ) sockaccept ( sock addr addrlen -- sock/err ) -- varies from bsd socks connect ( sock addr addrlen -- 0/err ) select ( numfds readfds writefds errfds timeout -- fd/err ) poll ( pollfds n timeout -- fd/err ) send ( sock a n flags -- n/err ) sendto ( sock a n flags addr addrlen -- n/err ) sendmsg ( sock msg flags -- n/err ) recv ( sock a n flags -- n/err ) recvfrom ( sock a n flags addr addrlen -- n/err ) recvmsg ( sock msg flags -- n/err ) gethostbyname ( hostnamez -- hostent/0 ) errno ( -- err ) -- ESP32 only as of v7.0.7.2 sockaddr ( "name" -- ) creates a sockaddr structure ->port@ ( a -- n ) get port from sockaddr ->port! ( n a -- ) set port in sockaddr ->addr@ ( a -- n ) get big-endian address from sockaddr ->addr! ( n a -- ) set big-endian address in sockaddr ip. ( n -- ) Print address as x.y.z.w IP address. ( Constants ) SOCK_STREAM SOCK_DGRAM SOCK_RAW AF_INET sizeof(sockaddr_in) SOL_SOCKET SO_REUSEADDR
WARNING: Danger ahead.
Snapshotting the dictionary may not be stable across reinstallations of the C build of Forth.
A collection of non-standard words is provided that allow snapshotting the dictionary and restoring it at startup, with a start word.
SAVE ( "name" -- ) Saves a snapshot of the current dictionary to a file.
RESTORE ( "name" -- ) Restore a snapshot from a file.
REMEMBER ( -- ) Save a snapshot to the default file
(./myforth or /spiffs/myforth on ESP32).
STARTUP: ( "name" -- ) Save a snapshot to the default file arranging for
"name" to be run on startup.
REVIVE ( -- ) Restore the default filename.
RESET ( -- ) Delete the default filename.
Here's an example usage:
: welcome ." Hello!" cr 100 0 do i . loop cr ; startup: welcome bye ( Next boot will run a custom startup message ) reset ( Reset removes the custom message )
The INTERNALS vocabulary has some additional words
for more control.
SAVE-NAME ( a n -- ) Save a snapshot if the current vocabulary to a file.
RESTORE-NAME ( a n -- ) Restore a snapshot from a file.
'COLD ( -- a ) Address of the word that will be run on startup.
REMEMBER-FILENAME ( -- a n ) Deferred word specifying the platform specific
default snapshot filename.
web-interface vocabulary.
server ( port -- ) Start web UI on port (used to implement webui).
Requires v7.0.6+
These words are inside thehttpd vocabulary.
server ( port -- ) Start an httpd on port. handleClient ( -- ) Get next request. path ( -- a n ) Request path, e.g. /foo method ( -- a n ) Request method, e.g. GET header ( a n -- a n ) Contents of header (or empty string). body ( -- a n ) Rquest body.
web-interface vocabulary.
server ( port -- ) Start telnet daemon on port.
Linux libraries and the operating system can be accessed via the use
of the DLSYM word. Functions can be requested by name from
particular modules. As the dynamic linking module is already loaded initially,
a 0 for the module allows the library loading function (dlopen)
to be loaded from Forth.
DLSYM ( module name-z -- fn )
See posix_main.c.
Native functions all called with CALL(n) (see Windows & Linux Calling below).
Various Linux calls including Xlib are imported in
posix.fs and
xlib.fs.
In addition, TYPE and KEY are connected to
stdin and stdout.
As unfortunately both Windows and Linux have system and library calls with
as many as 10 parameters (for example XCreateImage),
a collection of calling thunks is required.
A single varidic thunk would be ideal, but is hard to do without per platform
assembly language.
CALL0 ( fn -- n ) CALL1 ( n fn -- n ) CALL2 ( n n fn -- n ) CALL3 ( n n n fn -- n ) CALL4 ( n n n n fn -- n ) CALL5 ( n n n n n fn -- n ) CALL6 ( n n n n n n fn -- n ) CALL7 ( n n n n n n n fn -- n ) CALL7 ( n n n n n n n n fn -- n ) CALL9 ( n n n n n n n n n fn -- n ) CALL10 ( n n n n n n n n n n fn -- n )
See calling.h.