PNO and some other stuff

2 files changed, 80 insertions, 6 deletions

diff --git a/readme.md b/readme.md
index 7b813cd..0b89015 100644
--- a/readme.md
+++ b/readme.md
@@ -10,21 +10,35 @@ documentation and will be obvious or documented in the description.
 - `c`: one byte value
 - `n`: signed integer
 - `u`: unsigned integer
+- `z`: null-terminated string
 - `?`: boolean flag
 - `xt`: execution token
 - `ht`: header token
 - `""`: string in input buffer
 - `|`: 'or'
-- `,`: used to separate multiple stack effects when multiple are needed
+- `,`: separates multiple stack effects when multiple are needed
 
 ## Glossary
 
 the following is a list of words available in this forth.
+certain constants for linux system interaction are not documented;
+they are identical to their C versions.
 
 ### `!   ( u a -- )`
 store the 64 bit value u into the memory address a.
 
-### `#tib   ( -- a )`
+### `#   ( u -- u' )`
+add a numeric digit to the numeric output buffer
+by dividing u by `base` and appending the remainder.
+
+### `#>   ( u -- a u )`
+drop the remaining digit processing debris from the stack
+and return the numeric output buffer contents as a string.
+
+### `#pad   ( -- u )`
+length of the pad buffer.
+
+### `#tib   ( -- u )`
 variable containing the amount of characters in the input buffer.
 
 ### `'   ( "word" -- xt )`
@@ -77,7 +91,7 @@ add u2 to u1.
 ### `+!   ( a -- )`
 add one to the value at memory address a.
 
-### `+to   ( comp: "name" -- | intr: u "name" -- ) IMMEDIATE`
+### `+to   ( comp: "name" -- , intr: u "name" -- ) IMMEDIATE`
 compile or execute (depending on `state`) code to add u to the contents
 of a `value`. (in compile mode u is whatever was on the stack already.)
 
@@ -90,7 +104,7 @@ subtract u2 from u1.
 ### `-!   ( a -- )`
 subtract one from the value at memory address a.
 
-### `-to   ( comp: "name" -- | intr: u "name" -- ) IMMEDIATE`
+### `-to   ( comp: "name" -- , intr: u "name" -- ) IMMEDIATE`
 compile or execute (depending on `state`) code to subtract u from the contents
 of a `value`. (in compile mode u is whatever was on the stack already.)
 
@@ -129,9 +143,13 @@ fetch the 64 bit value at memory address a.
 ### `=   ( n1 n2 -- ? )`
 return true if n1 and n2 are equal.
 
+
 ### `<   ( n1 n2 -- ? )`
 return true if n1 is less than n2.
 
+### `<#   ( -- )`
+initialise the system for numeric output.
+
 ### `<=   ( n1 n2 -- ? )`
 return true if n1 is less than or equal to n2.
 
@@ -369,6 +387,12 @@ its very specific context (replacing core assembly words
 with better versions in forth), so it should be avoided
 in favour of `defer` and friends.
 
+### `hld   ( -- a )`
+the address of the beginning of the used section of the pad buffer.
+
+### `hold   ( c -- )`
+add the given charater into the numeric output buffer.
+
 ### `if   ( ? -- ) IMMEDIATE COMPILE-ONLY`
 if the flag is true, execute the following if statement,
 terminated by `else` or `then`.
@@ -416,6 +440,13 @@ perform bitwise OR on u1 and u2.
 ### `over   ( u1 u2 -- u1 u2 u1 )`
 copy the second-highest value on the stack and move it to the top of the stack.
 
+### `pad   ( -- a )`
+the address of the start of the pictured numeric output buffer.
+
+### `pad$   ( -- a )`
+the address of the end of the pictured numeric output buffer.
+useful because numeric output uses the buffer high-memory first.
+
 ### `parse   ( "name<c>" c -- a u )`
 parse one word from the input buffer,
 separated by a newline or the character c,
@@ -444,6 +475,12 @@ and activated with `privatise`.
 ### `privatise   ( -- )`
 activate a private section.
 
+### `r/o   ( -- 0 )`
+a constant, meaning 'read only', used for file I/O.
+
+### `r/w   ( -- 2 )`
+a constant, meaning 'read and write', used for file I/O.
+
 ### `r>   ( -- u ) ( R: u -- )`
 move a value from the return stack to the working stack.
 
@@ -470,6 +507,9 @@ the string data and length are stored inline in the definition.
 compile into user memory a copy of the given regular string
 converted to a null-terminated string.
 
+### `sign   ( n -- )`
+add a minus sign to the numeric output buffer if n is less than zero.
+
 ### `smudge   ( -- )`
 toggles the smudge bit on the xt in latest.
 
@@ -495,6 +535,13 @@ push the file descriptor of stdout to the stack.
 ### `swap   ( u1 u2 -- u2 u1 )`
 swap the two topmost values on the stack.
 
+### `sys-close   ( fd -- n )`
+perform a `close(2)` system call on the given file descriptor.
+
+### `sys-open   ( mode flag z -- n )`
+perform an `open(2)` system call on the file named
+in the null-terminated string z, using the given file mode and flags.
+
 ### `sys-read   ( u a fd -- n )`
 perform a `read(2)` system call, reading into the buffer `u a`
 from file descriptor `fd`.
@@ -545,7 +592,7 @@ conclude an if statement.
 ### `tib   ( -- a )`
 a variable containing the address of the current input buffer.
 
-### `to   ( comp: "name" -- | intr: u "name" -- ) IMMEDIATE`
+### `to   ( comp: "name" -- , intr: u "name" -- ) IMMEDIATE`
 compile or execute (depending on `state`) code to modify the contents
 of a `value`.
 
@@ -583,6 +630,9 @@ create a value called name, the initial value of which is u.
 ### `variable   ( "name" -- )`
 create a variable word, which yields an address that can be written and read.
 
+### `w/o   ( -- 1 )`
+a constant, meaning 'write only', used for file I/O.
+
 ### `while   ( ? -- ) IMMEDIAT COMPILE-ONLYE`
 if given flag is true, continue the current begin-while-repeat loop,
 otherwise branch to after.
@@ -625,3 +675,6 @@ but it diverges in a few notable places:
     this forth uses lower case word names for core words.
 - `find` takes `a u` instead of a counted string,
     and does not return 1 for immediate words.
+- PNO words (`<# # #>` etc.) work with single cell numbers.
+    this is because this forth has no double number support.
+    (128 bit integer arithmetic does not seem all that useful to me)
diff --git a/sanctuary.fs b/sanctuary.fs
index 15d5a0e..1aab4e2 100644
--- a/sanctuary.fs
+++ b/sanctuary.fs
@@ -111,6 +111,21 @@ decimal
 : munmap  11 syscall2 ;
 \ }}}
 
+\ NUMERIC OUTPUT {{{
+\ this buffer is also used as a temporary string buffer.
+255 constant #pad
+create pad 255 cells allot
+: pad$  pad #pad + ;
+variable hld
+
+: <#  pad$ hld ! ;
+: hold  1 hld -!  ( chr ) hld @ c! ;
+: sign  0< if [ char - ] literal hold then ;
+: #  base @ /mod swap 9 over < if 7 + then [ char 0 ] literal + hold ;
+: #s  begin # dup 0= until ;
+: #>  drop hld @ pad$ over - ;
+\ }}}
+
 \ I/O {{{
 0 constant stdin
 1 constant stdout
@@ -118,9 +133,15 @@ decimal
 
 : sys-write  0 syscall3 ;
 : sys-read  1 syscall3 ;
+: sys-open  2 syscall3 ;
+: sys-close  3 syscall1 ;
 
-: type  swap stdout 1 syscall3 drop ;
+: type  swap stdout sys-read drop ;
 : emit  sp 1 type drop ;
+
+0 constant r/o
+1 constant w/o
+2 constant r/w
 \ }}}
 
 bye