Aded extended commands and editor

CHANGELOG

@@ -1,3 +1,26 @@
+0.2.14
+
+- Add `rackedit` as a runtime dependency.
+- Add the Rash `edit` command, implemented by `coreutils-edit`.
+- Use RackEdit's `rkdt` as the default editor and map `edit --wait FILE` to `#:wait? #t`.
+- Add `current-coreutils-editor` so callers can dynamically select another editor procedure.
+- Rework the Scribble manual around the commands available in Rash, with each command documenting its internal Racket implementation.
+- Add non-GUI regression tests for editor dispatch and `--wait` translation.
+
+0.2.12
+
+- Add a portable `time` command for rash-coreutils commands and executables on PATH.
+- Report real, combined CPU, and Racket GC time to stderr so command stdout remains pipeline-safe.
+- Include completed subprocess CPU time in the reported CPU measurement.
+- Add package-index-safe regression coverage for command timing and stderr separation.
+
+0.2.11
+
+- Make head and tail scan fixed-size byte blocks instead of materializing complete lines.
+- Make tail scan seekable files backwards so memory use is independent of file and line size.
+- Spool tail input from stdin or multiple files to a temporary file instead of retaining lines in memory.
+- Add regression coverage for very long lines in head and tail.
+
 0.2.9
 
 - Make package-build tests independent of the directory from which raco test is invoked.

README.md

@@ -1,31 +1,63 @@
 # rash-coreutils
 
-Portable Unix-style core utilities for Rash, implemented in Racket.
+Portable Unix-style commands for Rash, implemented in Racket.
 
-Version 0.2.9 includes text/pipeline tools (`head`, `tail`, `wc`, `sort`, `uniq`,
-`cut`, `tee`, `tr`), path and filesystem helpers (`basename`, `dirname`,
-`realpath`, `readlink`, `stat`, `du`, `df`, `mktemp`), environment commands
-(`printenv`, `env`), and `date` backed by Gregor.
+Version 0.2.14 adds the `edit` command backed by the `rackedit` package and
+reworks the manual around the commands that are available directly in Rash.
+The manual now describes, per command, which internal `coreutils-*` Racket
+procedure implements it.
 
 Rash remains responsible for shell syntax such as globbing, pipelines and
 redirection. `rash-coreutils` additionally accepts Racket regular expressions as
 path selectors.
 
+## Editing
+
+`edit` opens one file using the editor configured by `current-coreutils-editor`.
+The default editor is RackEdit's `rkdt` procedure.
+
+```text
+edit notes.rkt
+edit --wait notes.rkt
+```
+
+`--wait` is passed to RackEdit as `#:wait? #t`. In ordinary Racket code a
+different editor can be selected dynamically by parameterizing
+`current-coreutils-editor` with a procedure that accepts a file path and the
+`#:wait?` keyword.
+
+## Command timing
+
+`time` executes one rash-coreutils command or executable and writes timing data
+to standard error. Command output therefore remains suitable for pipelines and
+redirection. The portable measurements are elapsed (`real`) time, combined CPU
+time (`cpu`) for Racket and completed subprocesses, and Racket garbage-collection
+time (`gc`).
+
+```text
+time head -n 100 large.txt
+time raco test tests/coreutils.rkt
+```
 
 ## Racket tooling
 
-`rash-coreutils` also exposes the `raco` command from the active Racket installation, without requiring `raco` to be on PATH.
+`rash-coreutils` also exposes the `raco` command from the active Racket
+installation, without requiring `raco` to be on PATH.
 
 ```text
 raco setup rash-coreutils
 raco pkg show
 ```
 
-In Racket expression mode, use `coreutils-raco`, for example `(coreutils-raco '(setup rash-coreutils))`. The name `raco` is reserved for the Rash command binding.
+In Racket expression mode, use `coreutils-raco`, for example
+`(coreutils-raco '(setup rash-coreutils))`. The name `raco` is reserved for the
+Rash command binding.
 
 ## Windows paths
 
-Commands that print paths use forward slashes on Windows. This keeps their textual output directly reusable in Rash line mode, where a backslash is an escape character. Internally, Racket path values remain native paths.
+Commands that print paths use forward slashes on Windows. This keeps their
+textual output directly reusable in Rash line mode, where a backslash is an
+escape character. Internally, Racket path values remain native paths.
 
 ```text
 pwd
@@ -35,4 +67,5 @@ mktemp
 C:/Users/hans/AppData/Local/Temp/tmp123
 ```
 
-A native Racket path value can still be passed directly, for example `ls (values (find-system-path 'temp-dir))`.
+A native Racket path value can still be passed directly, for example
+`ls (values (find-system-path 'temp-dir))`.

help

@@ -1,7 +1,7 @@
 #lang info
 
 (define pkg-authors '(hnmdijkema))
-(define version "0.1.6")
+(define version "0.2.14")
 (define license 'MIT)
 (define collection "rash-coreutils")
 (define pkg-desc
@@ -11,10 +11,10 @@
   '(("scrbl/rash-coreutils.scrbl" () (library 0))))
 
 (define deps
-  '("base" "rash"))
+  '("base" "rash" "gregor-lib" "rackedit"))
 
 (define build-deps
   '("racket-doc"
     "rackunit-lib"
     "scribble-lib"
-    "rash"))
+    "linea"))

info.rkt

@@ -1,7 +1,7 @@
 #lang info
 
 (define pkg-authors '(hnmdijkema))
-(define version "0.2.9")
+(define version "0.2.14")
 (define license 'MIT)
 (define collection "rash-coreutils")
 (define pkg-desc
@@ -11,7 +11,7 @@
   '(("scrbl/rash-coreutils.scrbl" () (library 0))))
 
 (define deps
-  '("base" "rash" "gregor-lib"))
+  '("base" "rash" "gregor-lib" "rackedit"))
 
 (define build-deps
   '("racket-doc"

main.rkt

@@ -4,6 +4,7 @@
          "private/extended.rkt"
          "private/commands.rkt"
          "private/racket-tools.rkt"
+         "private/editor.rkt"
          "private/dispatcher.rkt"
          "private/help.rkt"
          "private/aliases.rkt")
@@ -12,6 +13,7 @@
          (all-from-out "private/extended.rkt")
          (all-from-out "private/commands.rkt")
          (all-from-out "private/racket-tools.rkt")
+         (all-from-out "private/editor.rkt")
          (all-from-out "private/dispatcher.rkt")
          (all-from-out "private/help.rkt")
          (all-from-out "private/aliases.rkt"))

private/aliases.rkt

@@ -9,7 +9,7 @@
 
 (provide pwd ls mkdir rmdir rm cp mv cat touch echo which
          head tail wc sort uniq cut tee tr basename dirname realpath readlink
-         stat du df mktemp printenv env date help raco)
+         stat du df mktemp printenv env date time edit help raco)
 
 (define (make-command-procedure name)
   (λ args
@@ -45,6 +45,8 @@
 (define printenv-command (make-command-procedure 'printenv))
 (define env-command (make-command-procedure 'env))
 (define date-command (make-command-procedure 'date))
+(define time-command (make-command-procedure 'time))
+(define edit-command (make-command-procedure 'edit))
 (define raco-command coreutils-raco)
 
 (define (help-command . args)
@@ -131,5 +133,7 @@
 (define-pipeline-alias printenv (make-coreutils-alias #'printenv-command))
 (define-pipeline-alias env      (make-env-alias #'env-command))
 (define-pipeline-alias date     (make-coreutils-alias #'date-command))
+(define-pipeline-alias time     (make-coreutils-alias #'time-command))
+(define-pipeline-alias edit     (make-coreutils-alias #'edit-command))
 (define-pipeline-alias help     (make-coreutils-alias #'help-command))
 (define-pipeline-alias raco     (make-coreutils-alias #'raco-command))

private/commands.rkt

@@ -2,7 +2,8 @@
 
 (require "coreutils.rkt"
          "extended.rkt"
-         "racket-tools.rkt")
+         "racket-tools.rkt"
+         "editor.rkt")
 
 (provide (struct-out coreutils-command)
          coreutils-commands
@@ -42,6 +43,8 @@
    (coreutils-command 'printenv coreutils-printenv 'rash-coreutils-printenv)
    (coreutils-command 'env coreutils-env 'rash-coreutils-env)
    (coreutils-command 'date coreutils-date 'rash-coreutils-date)
+   (coreutils-command 'time coreutils-time 'rash-coreutils-time)
+   (coreutils-command 'edit coreutils-edit 'rash-coreutils-edit)
    (coreutils-command 'raco coreutils-raco 'rash-coreutils-raco)))
 
 (define (find-coreutils-command name)

private/editor.rkt

@@ -0,0 +1,66 @@
+#lang racket/base
+
+(require racket/format
+         racket/path
+         racket/string
+         rackedit)
+
+(provide coreutils-edit
+         current-coreutils-editor)
+
+(define current-coreutils-editor
+  (make-parameter
+   rkdt
+   (λ (editor)
+     (unless (procedure? editor)
+       (raise-argument-error 'current-coreutils-editor "procedure?" editor))
+     editor)))
+
+(define (arg->path arg)
+  (cond
+    [(path? arg) arg]
+    [(string? arg) (string->path arg)]
+    [(symbol? arg) (string->path (symbol->string arg))]
+    [else
+     (raise-argument-error
+      'edit
+      "path, string, or symbol"
+      arg)]))
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+; goal   : Open one file in the editor configured for rash-coreutils.
+; pre    : args contains exactly one filename and optionally --wait.
+; post   : The configured editor has been invoked once. With --wait, the
+;          command does not return until the editor procedure returns.
+; result : (void).
+; internals:
+;          current-coreutils-editor defaults to rackedit's rkdt procedure.
+;          The --wait flag is translated to rkdt's #:wait? keyword.
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+(define (coreutils-edit . args)
+  (define wait? #f)
+  (define reversed-paths '())
+
+  (for ([arg (in-list args)])
+    (define text (~a arg))
+    (cond
+      [(string=? text "--wait")
+       (set! wait? #t)]
+      [(string-prefix? text "-")
+       (raise-arguments-error 'edit
+                              "unsupported option"
+                              "option" text)]
+      [else
+       (set! reversed-paths (cons (arg->path arg) reversed-paths))]))
+
+  (define paths (reverse reversed-paths))
+  (unless (or (= (length paths) 1) (= (length paths) 0))
+    (raise-arguments-error 'edit
+                           "expected exactly zero or one file"
+                           "arguments" args))
+
+  (if (null? paths)
+      ((current-coreutils-editor) #:wait? wait?)
+      ((current-coreutils-editor) (car paths) #:wait? wait?))
+  
+  (void))

scrbl/rash-coreutils.scrbl

@@ -1,6 +1,7 @@
 #lang scribble/manual
 
 @(require (for-label racket/base
+                     (only-in rackedit rkdt)
                      (only-in rash-coreutils
                               coreutils-pwd coreutils-ls coreutils-mkdir coreutils-rmdir
                               coreutils-rm coreutils-cp coreutils-mv coreutils-cat
@@ -10,140 +11,506 @@
                               coreutils-dirname coreutils-realpath coreutils-readlink
                               coreutils-stat coreutils-du coreutils-df coreutils-mktemp
                               coreutils-printenv coreutils-env coreutils-date
-                              raco
-                              coreutils-raco)))
+                              coreutils-time coreutils-edit current-coreutils-editor
+                              coreutils-help dispatch-coreutils-command
+                              raco coreutils-raco)))
 
 @title{rash-coreutils}
 @author["Hans Dijkema / hans@dijkewijk.nl"]
 
 @defmodule[rash-coreutils]
 
-@bold{rash-coreutils} provides platform-independent Unix-style shell commands
-for Rash. The commands are implemented in Racket, so common shell utilities do
-not depend on @tt{cmd.exe}, PowerShell, or Unix executables being installed.
+@bold{rash-coreutils} provides platform-independent Unix-style commands for
+Rash. The user-facing API is the set of commands that can be written directly
+in Rash line mode. Most commands are implemented by ordinary Racket procedures,
+so they do not depend on @tt{cmd.exe}, PowerShell, or Unix utility executables.
 
 Rash remains responsible for shell syntax such as pipelines, globbing, tilde
-expansion, variable expansion, and redirection. @bold{rash-coreutils} supplies
-the commands themselves plus Racket-specific additions such as regular-expression
-path selectors.
+expansion, variable expansion, and redirection. The command aliases provided by
+this package preserve those Rash semantics and then dispatch to the internal
+Racket implementation.
 
-@section{Commands}
+@section{How a Rash command is executed}
 
-The package provides @tt{pwd}, @tt{ls}, @tt{mkdir}, @tt{rmdir}, @tt{rm},
-@tt{cp}, @tt{mv}, @tt{cat}, @tt{touch}, @tt{echo}, @tt{which}, @tt{head},
-@tt{tail}, @tt{wc}, @tt{sort}, @tt{uniq}, @tt{cut}, @tt{tee}, @tt{tr},
-@tt{basename}, @tt{dirname}, @tt{realpath}, @tt{readlink}, @tt{stat}, @tt{du},
-@tt{df}, @tt{mktemp}, @tt{printenv}, @tt{env}, @tt{date}, @tt{raco}, and @tt{help}.
+For a normal command such as
+
+@verbatim{
+ls -l *.rkt
+}
+
+Rash first processes its line syntax and pipeline semantics. The @tt{ls} alias
+then calls @racket[dispatch-coreutils-command], which looks up the registered
+command and invokes @racket[coreutils-ls]. Arguments that are Racket regular
+expressions are expanded by the rash-coreutils dispatcher before the internal
+procedure is called.
+
+This means the shell command is the primary interface, while procedures such as
+@racket[coreutils-ls] are the implementation API and are also available to
+ordinary Racket code.
 
 The option set is deliberately smaller than GNU coreutils. Unsupported options
-raise an error instead of silently approximating another command's behavior.
+raise an error instead of silently approximating behavior that is not
+implemented.
 
-@section{Racket procedures}
-
-Each shell command has an explicitly named Racket procedure. All procedures
-write to the normal current ports so Rash pipeline and redirection semantics
-continue to work.
+@section{Filesystem commands}
 
 @index["rash-coreutils-pwd"]
-@defproc[(coreutils-pwd) void?]{Writes the current directory.}
+@subsection{@tt{pwd}}
+
+@verbatim{
+pwd
+}
+
+Writes the current directory. The command accepts no arguments.
+
+Internally, @tt{pwd} dispatches to @racket[coreutils-pwd].
+
+@defproc[(coreutils-pwd) void?]{Writes @racket[current-directory] using a Rash-friendly textual path.}
 
 @index["rash-coreutils-ls"]
-@defproc[(coreutils-ls [arg any/c] ...) void?]{Lists paths. Supports @tt{-a}, @tt{-l}, and their long forms.}
+@subsection{@tt{ls}}
+
+@verbatim{
+ls
+ls -l
+ls -a
+ls -la
+ls *.rkt
+ls #px"^info[0-9]+[.]rkt$"
+}
+
+Lists files and directories. @tt{-a}/@tt{--all} includes hidden names and
+@tt{-l}/@tt{--long} writes the portable long form used by this package. Rash
+performs normal glob expansion. A Racket regular-expression value is an
+additional rash-coreutils path selector and is matched against names in the
+current directory.
+
+Internally, @tt{ls} dispatches to @racket[coreutils-ls].
+
+@defproc[(coreutils-ls [arg any/c] ...) void?]{Implements the listing after Rash and dispatcher argument handling.}
 
 @index["rash-coreutils-mkdir"]
-@defproc[(coreutils-mkdir [arg any/c] ...) void?]{Creates directories. Supports @tt{-p}.}
+@subsection{@tt{mkdir}}
+
+@verbatim{
+mkdir work
+mkdir -p build/output
+}
+
+Creates one or more directories. @tt{-p}/@tt{--parents} creates missing parent
+directories.
+
+Internally, @tt{mkdir} dispatches to @racket[coreutils-mkdir].
+
+@defproc[(coreutils-mkdir [arg any/c] ...) void?]{Creates the requested directories.}
 
 @index["rash-coreutils-rmdir"]
+@subsection{@tt{rmdir}}
+
+@verbatim{
+rmdir empty-directory
+}
+
+Removes one or more empty directories. No options are currently supported.
+
+Internally, @tt{rmdir} dispatches to @racket[coreutils-rmdir].
+
 @defproc[(coreutils-rmdir [arg any/c] ...) void?]{Removes empty directories.}
 
 @index["rash-coreutils-rm"]
-@defproc[(coreutils-rm [arg any/c] ...) void?]{Removes paths. Supports recursive and force options.}
+@subsection{@tt{rm}}
+
+@verbatim{
+rm file.txt
+rm -r directory
+rm -rf generated
+}
+
+Removes files or links. Directories require @tt{-r}, @tt{-R}, or
+@tt{--recursive}. @tt{-f}/@tt{--force} suppresses an error for a missing path.
+The combined forms @tt{-rf}, @tt{-fr}, @tt{-Rf}, and @tt{-fR} are supported.
+
+Internally, @tt{rm} dispatches to @racket[coreutils-rm].
+
+@defproc[(coreutils-rm [arg any/c] ...) void?]{Removes the requested paths.}
 
 @index["rash-coreutils-cp"]
-@defproc[(coreutils-cp [arg any/c] ...) void?]{Copies a source to a destination. Directory copies require @tt{-r}.}
+@subsection{@tt{cp}}
+
+@verbatim{
+cp source.txt copy.txt
+cp -r source-directory copy-directory
+}
+
+Copies exactly one source to one destination. Directory copies require
+@tt{-r}, @tt{-R}, or @tt{--recursive}.
+
+Internally, @tt{cp} dispatches to @racket[coreutils-cp].
+
+@defproc[(coreutils-cp [arg any/c] ...) void?]{Copies a file or, in recursive mode, a directory tree.}
 
 @index["rash-coreutils-mv"]
+@subsection{@tt{mv}}
+
+@verbatim{
+mv old-name.txt new-name.txt
+}
+
+Moves or renames exactly one source path to one destination path.
+
+Internally, @tt{mv} dispatches to @racket[coreutils-mv].
+
 @defproc[(coreutils-mv [source any/c] [destination any/c]) void?]{Moves or renames a path.}
 
-@index["rash-coreutils-cat"]
-@defproc[(coreutils-cat [arg any/c] ...) void?]{Copies files, or standard input, to standard output.}
-
 @index["rash-coreutils-touch"]
-@defproc[(coreutils-touch [arg any/c] ...) void?]{Updates modification times or creates empty files.}
+@subsection{@tt{touch}}
 
-@index["rash-coreutils-echo"]
-@defproc[(coreutils-echo [arg any/c] ...) void?]{Writes arguments separated by spaces.}
+@verbatim{
+touch notes.txt
+}
 
-@index["rash-coreutils-which"]
-@defproc[(coreutils-which [arg any/c] ...) void?]{Finds executables using Racket's executable search.}
+Creates missing files and updates the modification time of existing files. No
+options are currently supported.
 
-@index["rash-coreutils-head"]
-@defproc[(coreutils-head [arg any/c] ...) void?]{Writes the first lines of input. Supports @tt{-n}.}
+Internally, @tt{touch} dispatches to @racket[coreutils-touch].
 
-@index["rash-coreutils-tail"]
-@defproc[(coreutils-tail [arg any/c] ...) void?]{Writes the last lines of input. Supports @tt{-n}.}
-
-@index["rash-coreutils-wc"]
-@defproc[(coreutils-wc [arg any/c] ...) void?]{Counts lines, words, and bytes. Supports @tt{-l}, @tt{-w}, and @tt{-c}.}
-
-@index["rash-coreutils-sort"]
-@defproc[(coreutils-sort [arg any/c] ...) void?]{Sorts lines. Supports @tt{-r} and @tt{-n}.}
-
-@index["rash-coreutils-uniq"]
-@defproc[(coreutils-uniq [arg any/c] ...) void?]{Collapses adjacent duplicate lines. Supports @tt{-c}.}
-
-@index["rash-coreutils-cut"]
-@defproc[(coreutils-cut [arg any/c] ...) void?]{Selects one delimited field with @tt{-d} and @tt{-f}.}
-
-@index["rash-coreutils-tee"]
-@defproc[(coreutils-tee [arg any/c] ...) void?]{Copies standard input to standard output and files. Supports @tt{-a}.}
-
-@index["rash-coreutils-tr"]
-@defproc[(coreutils-tr [arg any/c] ...) void?]{Translates characters from standard input. Character ranges such as @tt{a-z}, @tt{A-Z}, and @tt{0-9} are expanded. @tt{-d} deletes characters and @tt{-s} squeezes repeated characters.}
+@defproc[(coreutils-touch [arg any/c] ...) void?]{Touches one or more files.}
 
 @index["rash-coreutils-basename"]
+@subsection{@tt{basename}}
+
+@verbatim{
+basename a/b/file.txt
+}
+
+Writes the final component of one path.
+
+Internally, @tt{basename} dispatches to @racket[coreutils-basename].
+
 @defproc[(coreutils-basename [path any/c]) void?]{Writes the final path component.}
 
 @index["rash-coreutils-dirname"]
+@subsection{@tt{dirname}}
+
+@verbatim{
+dirname a/b/file.txt
+}
+
+Writes the directory portion of one path.
+
+Internally, @tt{dirname} dispatches to @racket[coreutils-dirname].
+
 @defproc[(coreutils-dirname [path any/c]) void?]{Writes the directory portion of a path.}
 
 @index["rash-coreutils-realpath"]
-@defproc[(coreutils-realpath [path any/c]) void?]{Writes a complete simplified path.}
+@subsection{@tt{realpath}}
+
+@verbatim{
+realpath relative/path
+}
+
+Writes a complete simplified path with filesystem links resolved where the
+current filesystem supports that resolution.
+
+Internally, @tt{realpath} dispatches to @racket[coreutils-realpath].
+
+@defproc[(coreutils-realpath [path any/c]) void?]{Writes the complete simplified path.}
 
 @index["rash-coreutils-readlink"]
-@defproc[(coreutils-readlink [path any/c]) void?]{Resolves a symbolic link.}
+@subsection{@tt{readlink}}
+
+@verbatim{
+readlink link-name
+}
+
+Writes the target of one symbolic link and reports an error when the supplied
+path is not a link.
+
+Internally, @tt{readlink} dispatches to @racket[coreutils-readlink].
+
+@defproc[(coreutils-readlink [path any/c]) void?]{Writes the resolved symbolic-link target.}
 
 @index["rash-coreutils-stat"]
+@subsection{@tt{stat}}
+
+@verbatim{
+stat file.txt
+stat file.txt directory
+}
+
+Writes portable type, size, and modification information for one or more paths.
+
+Internally, @tt{stat} dispatches to @racket[coreutils-stat].
+
 @defproc[(coreutils-stat [path any/c] ...) void?]{Writes basic portable path metadata.}
 
 @index["rash-coreutils-du"]
-@defproc[(coreutils-du [arg any/c] ...) void?]{Calculates recursive file size. Supports @tt{-h}.}
-
-@index["rash-coreutils-df"]
-@defproc[(coreutils-df) void?]{Lists filesystem roots. Racket has no portable API for total and free filesystem capacity, so this initial implementation deliberately does not invent platform-specific subprocess fallbacks.}
-
-@index["rash-coreutils-mktemp"]
-@defproc[(coreutils-mktemp [arg any/c] ...) void?]{Creates a temporary file, or a directory with @tt{-d}, and writes its path.}
-
-@index["rash-coreutils-printenv"]
-@defproc[(coreutils-printenv [name any/c] ...) void?]{Writes environment variables.}
-
-@index["rash-coreutils-env"]
-@defproc[(coreutils-env [arg any/c] ...) void?]{Creates a copied environment, applies leading @tt{NAME=value} assignments, and either writes that environment or runs the remaining command in it. Racket values are converted to environment strings.}
-
-The Rash form can mix shell-style assignment names with Racket expressions:
+@subsection{@tt{du}}
 
 @verbatim{
+du
+du -h directory
+}
+
+Writes the accumulated file size of each requested path. With no path, the
+current directory is used. @tt{-h}/@tt{--human-readable} formats the size using
+binary K, M, and G units. Symbolic links are not followed.
+
+Internally, @tt{du} dispatches to @racket[coreutils-du].
+
+@defproc[(coreutils-du [arg any/c] ...) void?]{Calculates recursive file size.}
+
+@index["rash-coreutils-df"]
+@subsection{@tt{df}}
+
+@verbatim{
+df
+}
+
+Lists filesystem roots visible to Racket. This portable implementation does not
+invent platform-specific subprocess fallbacks for total and free capacity.
+
+Internally, @tt{df} dispatches to @racket[coreutils-df].
+
+@defproc[(coreutils-df) void?]{Lists filesystem roots.}
+
+@index["rash-coreutils-mktemp"]
+@subsection{@tt{mktemp}}
+
+@verbatim{
+mktemp
+mktemp -d
+mktemp "rash-coreutils-~a"
+}
+
+Creates a unique temporary file and writes its path. @tt{-d}/@tt{--directory}
+creates a directory instead. An optional non-option argument is used as the
+Racket temporary-file template.
+
+Internally, @tt{mktemp} dispatches to @racket[coreutils-mktemp].
+
+@defproc[(coreutils-mktemp [arg any/c] ...) void?]{Creates a temporary file or directory and writes its path.}
+
+@section{Text and pipeline commands}
+
+@index["rash-coreutils-cat"]
+@subsection{@tt{cat}}
+
+@verbatim{
+cat file.txt
+cat first.txt second.txt
+producer | cat
+}
+
+Copies files to standard output. With no file arguments, it copies standard
+input. This makes the implementation usable in Rash pipelines without special
+pipeline code.
+
+Internally, @tt{cat} dispatches to @racket[coreutils-cat].
+
+@defproc[(coreutils-cat [arg any/c] ...) void?]{Copies file or standard-input bytes to the current output port.}
+
+@index["rash-coreutils-echo"]
+@subsection{@tt{echo}}
+
+@verbatim{
+echo hello world
+}
+
+Writes its arguments separated by spaces and terminates the result with a
+newline.
+
+Internally, @tt{echo} dispatches to @racket[coreutils-echo].
+
+@defproc[(coreutils-echo [arg any/c] ...) void?]{Writes the textual representation of the arguments.}
+
+@index["rash-coreutils-head"]
+@subsection{@tt{head}}
+
+@verbatim{
+head file.txt
+head -n 20 file.txt
+}
+
+Writes the first lines of files or standard input. @tt{-n}/@tt{--lines}
+selects a non-negative line count; the default is 10. Input is scanned in fixed
+size byte blocks so memory use does not grow with file size or an individual
+line length.
+
+Internally, @tt{head} dispatches to @racket[coreutils-head].
+
+@defproc[(coreutils-head [arg any/c] ...) void?]{Writes the requested first lines.}
+
+@index["rash-coreutils-tail"]
+@subsection{@tt{tail}}
+
+@verbatim{
+tail file.txt
+tail -n 20 file.txt
+}
+
+Writes the last lines of files or standard input. @tt{-n}/@tt{--lines} selects
+a non-negative line count; the default is 10. Seekable files are scanned
+backwards in fixed-size byte blocks. Input that cannot be scanned backwards is
+spooled to a temporary file, keeping memory use independent of input size and
+line length.
+
+Internally, @tt{tail} dispatches to @racket[coreutils-tail].
+
+@defproc[(coreutils-tail [arg any/c] ...) void?]{Writes the requested last lines.}
+
+@index["rash-coreutils-wc"]
+@subsection{@tt{wc}}
+
+@verbatim{
+wc file.txt
+wc -l file.txt
+wc -w file.txt
+wc -c file.txt
+}
+
+Counts lines, words, and bytes. @tt{-l} selects lines, @tt{-w} words, and
+@tt{-c}/@tt{--bytes} bytes. With no count options all three values are written.
+
+Internally, @tt{wc} dispatches to @racket[coreutils-wc].
+
+@defproc[(coreutils-wc [arg any/c] ...) void?]{Counts input using bounded streaming buffers.}
+
+@index["rash-coreutils-sort"]
+@subsection{@tt{sort}}
+
+@verbatim{
+sort file.txt
+sort -r file.txt
+sort -n numbers.txt
+}
+
+Sorts input lines. @tt{-r}/@tt{--reverse} reverses the ordering and
+@tt{-n}/@tt{--numeric-sort} uses numeric keys. Large input is divided into
+bounded in-memory runs and merged through temporary files.
+
+Internally, @tt{sort} dispatches to @racket[coreutils-sort].
+
+@defproc[(coreutils-sort [arg any/c] ...) void?]{Sorts lines without retaining the complete input in memory.}
+
+@index["rash-coreutils-uniq"]
+@subsection{@tt{uniq}}
+
+@verbatim{
+uniq sorted.txt
+uniq -c sorted.txt
+}
+
+Collapses adjacent duplicate lines. @tt{-c}/@tt{--count} prefixes each output
+line with its run count. As with the Unix command, input should already be
+grouped when non-adjacent equal lines must also be collapsed.
+
+Internally, @tt{uniq} dispatches to @racket[coreutils-uniq].
+
+@defproc[(coreutils-uniq [arg any/c] ...) void?]{Collapses adjacent duplicate lines.}
+
+@index["rash-coreutils-cut"]
+@subsection{@tt{cut}}
+
+@verbatim{
+cut -f 2 data.txt
+cut -d ";" -f 3 data.txt
+}
+
+Writes one delimited field from each input line. @tt{-f}/@tt{--fields} is
+required and currently accepts one positive field number. @tt{-d}/@tt{--delimiter}
+changes the delimiter from the default tab.
+
+Internally, @tt{cut} dispatches to @racket[coreutils-cut].
+
+@defproc[(coreutils-cut [arg any/c] ...) void?]{Selects one field from each input line.}
+
+@index["rash-coreutils-tee"]
+@subsection{@tt{tee}}
+
+@verbatim{
+producer | tee output.txt
+producer | tee -a output.txt
+}
+
+Copies standard input to standard output and to each named file.
+@tt{-a}/@tt{--append} appends instead of replacing existing file content.
+
+Internally, @tt{tee} dispatches to @racket[coreutils-tee].
+
+@defproc[(coreutils-tee [arg any/c] ...) void?]{Copies the current input stream to the current output and files.}
+
+@index["rash-coreutils-tr"]
+@subsection{@tt{tr}}
+
+@verbatim{
+echo abc | tr a-z A-Z
+echo a1b2c3 | tr -d 0-9
+echo "a   b" | tr -s " "
+}
+
+Translates characters from standard input. Simple ranges such as @tt{a-z},
+@tt{A-Z}, and @tt{0-9} are expanded. @tt{-d}/@tt{--delete} deletes selected
+characters and @tt{-s}/@tt{--squeeze-repeats} squeezes repeated selected
+characters. @tt{-ds} and @tt{-sd} are also accepted.
+
+Internally, @tt{tr} dispatches to @racket[coreutils-tr].
+
+@defproc[(coreutils-tr [arg any/c] ...) void?]{Translates, deletes, or squeezes characters from the current input port.}
+
+@section{Environment, time, and executable commands}
+
+@index["rash-coreutils-which"]
+@subsection{@tt{which}}
+
+@verbatim{
+which git
+which racket
+}
+
+Finds commands using Racket's executable search and writes the resolved path.
+
+Internally, @tt{which} dispatches to @racket[coreutils-which].
+
+@defproc[(coreutils-which [arg any/c] ...) void?]{Finds one or more executables on @tt{PATH}.}
+
+@index["rash-coreutils-printenv"]
+@subsection{@tt{printenv}}
+
+@verbatim{
+printenv
+printenv PATH
+}
+
+Writes the complete current environment or the values of selected variables.
+A missing selected variable produces no output.
+
+Internally, @tt{printenv} dispatches to @racket[coreutils-printenv].
+
+@defproc[(coreutils-printenv [name any/c] ...) void?]{Writes environment-variable values from @racket[current-environment-variables].}
+
+@index["rash-coreutils-env"]
+@subsection{@tt{env}}
+
+@verbatim{
+env NAME=value printenv NAME
 (define x 42)
 env ANSWER=(values x) printenv ANSWER
 }
 
-A parenthesized expression in Rash line mode is ordinary Racket code. Therefore
-the value after an empty @tt{NAME=} token can be a number, symbol, path, string,
-or another printable Racket value.
+Creates a copy of the current environment, applies leading @tt{NAME=value}
+assignments, and either writes the resulting environment or runs the remaining
+command in it. A parenthesized expression in Rash line mode is ordinary Racket
+code, so the value following an empty @tt{NAME=} token can be a Racket value.
+Registered rash-coreutils commands are tried before an executable on @tt{PATH}.
+
+Internally, the @tt{env} Rash alias first preserves Racket expressions in
+assignment values and then dispatches to @racket[coreutils-env].
+
+@defproc[(coreutils-env [arg any/c] ...) void?]{Applies temporary environment assignments and optionally runs a command.}
 
 @index["rash-coreutils-date"]
-@defproc[(coreutils-date [arg any/c] ...) void?]{Writes the current date and time using Gregor. Supports @tt{-u}/@tt{--utc}, @tt{-I}/@tt{--iso}, @tt{--tz ZONE}, and @tt{--format CLDR-PATTERN}. The format pattern follows Gregor's CLDR syntax rather than pretending to implement every GNU @tt{date} format escape.}
+@subsection{@tt{date}}
 
 @verbatim{
 date
@@ -152,47 +519,90 @@ date --utc --iso
 date --tz Europe/Amsterdam --format "yyyy-MM-dd HH:mm:ss"
 }
 
-@index["rash-coreutils-raco"]
-@defproc[(raco [arg any/c] ...) void?]{Runs @tt{raco} from the current Racket installation. The executable is resolved from the active Racket installation before PATH is considered, so it also works on Windows when @tt{raco.exe} is not on PATH. Arguments may be strings, symbols, paths, numbers, or nested lists. With no arguments, the underlying @tt{raco} program is invoked without a subcommand.}
+Writes the current date and time using Gregor. @tt{-u}/@tt{--utc} selects UTC,
+@tt{-I}/@tt{--iso}/@tt{--iso-8601} selects ISO output, @tt{--tz ZONE} selects a
+time zone, and @tt{--format CLDR-PATTERN} uses Gregor's CLDR formatting syntax.
 
-@defproc[(coreutils-raco [arg any/c] ...) void?]{Explicit implementation name for @racket[raco].}
+Internally, @tt{date} dispatches to @racket[coreutils-date].
+
+@defproc[(coreutils-date [arg any/c] ...) void?]{Writes the current date and time in the requested representation.}
+
+@index["rash-coreutils-time"]
+@subsection{@tt{time}}
+
+@verbatim{
+time head -n 100 large.txt
+time raco test tests/coreutils.rkt
+}
+
+Executes one registered rash-coreutils command or an executable on @tt{PATH} and
+writes timing data to standard error. The portable measurements are elapsed
+@tt{real} time, combined @tt{cpu} time for Racket and completed subprocesses,
+and Racket @tt{gc} time. Standard output from the timed command remains usable
+in pipelines and redirections.
+
+Internally, @tt{time} dispatches to @racket[coreutils-time].
+
+@defproc[(coreutils-time [command any/c] [arg any/c] ...) void?]{Runs and measures a command.}
+
+@index["rash-coreutils-raco"]
+@subsection{@tt{raco}}
 
 @verbatim{
 raco setup rash-coreutils
 raco pkg show
 }
 
-The same @racket[raco] binding is a normal Racket procedure, so expression-mode code can use @racket[(raco '(setup rash-coreutils))]. The explicit implementation name @racket[coreutils-raco] is also exported.
+Runs @tt{raco} from the active Racket installation. The executable is resolved
+from that installation before @tt{PATH} is considered, which avoids accidentally
+using @tt{raco} from another Racket installation and also works on Windows when
+@tt{raco.exe} is not on @tt{PATH}.
 
-@section{Path selection}
+The Rash command calls @racket[coreutils-raco]. The exported @racket[raco]
+binding is the Rash-facing command binding; ordinary Racket code can call
+@racket[coreutils-raco] explicitly.
 
-Shell-style argument expansion remains Rash's responsibility. The aliases expand
-back into Rash's @tt{=unix-pipe=} operator, preserving Rash globbing, tilde
-expansion, and @tt{$} expansion.
+@defproc[(coreutils-raco [arg any/c] ...) void?]{Runs the active installation's @tt{raco} executable.}
+
+@section{Editor command}
+
+@index["rash-coreutils-edit"]
+@subsection{@tt{edit}}
 
 @verbatim{
-ls *.rkt
-ls -l info*
-cat info*
+edit notes.rkt
+edit --wait notes.rkt
 }
 
-Regular-expression values are an additional @bold{rash-coreutils} selector. A
-@racket[#rx""] or @racket[#px""] value is matched against entry names in the
-current directory.
+Opens exactly one file in the editor configured for rash-coreutils. By default,
+the editor is RackEdit's @racket[rkdt] procedure. Without @tt{--wait}, RackEdit
+opens the editor and the Rash command can continue. With @tt{--wait}, the flag
+is translated to @racket[#:wait?] @racket[#t], so the command returns only after
+the editor procedure returns.
+
+Internally, @tt{edit} dispatches to @racket[coreutils-edit]. The implementation
+calls the procedure stored in @racket[current-coreutils-editor] with the file
+path and a @racket[#:wait?] keyword.
+
+@defproc[(coreutils-edit [arg any/c] ...) void?]{Parses @tt{--wait}, validates that exactly one file was supplied, and invokes @racket[current-coreutils-editor].}
+
+@defthing[current-coreutils-editor parameter?]{
+A parameter whose default value is @racket[rkdt]. The configured procedure must
+accept one file path and the optional keyword @racket[#:wait?]. A wrapper can be
+used to select a different editor for a dynamic extent.
+}
 
 @verbatim{
-ls #px"^info[0-9]+[.]rkt$"
+(parameterize
+    ([current-coreutils-editor
+      (λ (filename #:wait? [wait? #f])
+        ...)])
+  ...)
 }
 
+@section{Help command}
 
-@section{Windows paths}
-
-On Windows, commands that write path names use forward slashes in their textual output. Rash treats backslashes as escape characters in line mode, so a printed path such as @tt{C:/Users/name/AppData/Local/Temp/file} can be copied directly into another Rash command. Racket path values themselves remain native and can be passed directly to a command through a Racket expression.
-
-@section{Help}
-
-@tt{help} uses Racket's documentation search through @tt{raco docs}. Registered
-commands use package-specific index terms such as @tt{rash-coreutils-ls}.
+@subsection{@tt{help}}
 
 @verbatim{
 help
@@ -201,10 +611,49 @@ ls --help
 help directory-list
 }
 
+With no argument, @tt{help} writes the registered rash-coreutils command names.
+For a registered command, it searches Racket documentation using the command's
+package-specific index term, for example @tt{rash-coreutils-ls}. Other terms are
+passed directly to Racket's documentation search. Supplying @tt{--help} to a
+registered command uses the same mechanism.
+
+The @tt{help} alias calls @racket[coreutils-help] directly. The normal command
+dispatcher intercepts @tt{--help} before invoking the command implementation.
+
+@defproc[(coreutils-help [arg any/c] ...) void?]{Lists commands or opens Racket documentation for one search term.}
+
+@section{Path selection and Rash expansion}
+
+Normal shell-style argument expansion remains Rash's responsibility. The aliases
+expand back into Rash's pipeline machinery, preserving globbing, tilde expansion,
+variable expansion, pipelines, and redirection.
+
+@verbatim{
+ls *.rkt
+ls -l info*
+cat info* | wc -l
+}
+
+Racket regular-expression values are an additional rash-coreutils selector. A
+@racket[#rx""] or @racket[#px""] value is matched against entry names in the
+current directory before the internal command procedure is called.
+
+@verbatim{
+ls #px"^info[0-9]+[.]rkt$"
+}
+
+@section{Windows paths}
+
+On Windows, commands that write path names use forward slashes in their textual
+output. Rash treats backslashes as escape characters in line mode, so a printed
+path such as @tt{C:/Users/name/AppData/Local/Temp/file} can be copied directly
+into another Rash command. Racket path values themselves remain native and can
+be passed directly to a command through a Racket expression.
+
 @section{Capturing and redirecting output}
 
-Commands use normal ports. Rash can therefore capture or redirect them without
-special support in this package.
+The internal Racket procedures use normal current ports. Rash can therefore
+capture, pipe, or redirect command output without command-specific support.
 
 @verbatim{
 (define git-path { which git |> read-line })
@@ -216,5 +665,5 @@ cat info.rkt &>! copy.rkt
 
 The command names and common options follow Unix conventions, but this package
 does not claim complete GNU coreutils compatibility. Platform-independent
-behavior, predictable Rash scripting, and useful integration with Racket values
-are the primary goals.
+behavior, predictable Rash scripting, and integration with Racket values are
+the primary goals.

tests/coreutils.rkt

@@ -9,6 +9,7 @@
          "../private/dispatcher.rkt"
          "../private/help.rkt"
          "../private/racket-tools.rkt"
+         "../private/editor.rkt"
          "../private/env-support.rkt")
 
 (define (capture-output procedure . args)
@@ -95,8 +96,36 @@
      (check-equal? (coreutils-help-search-term 'directory-list)
                    "directory-list")
      (check-equal? (coreutils-help-search-term 'raco) "rash-coreutils-raco")
+     (check-equal? (coreutils-help-search-term 'edit) "rash-coreutils-edit")
      (check-true (path? (find-raco-executable)))
      (check-true (procedure? coreutils-raco))
+     (check-true (procedure? (current-coreutils-editor)))
+
+     (define edit-call #f)
+     (parameterize
+         ([current-coreutils-editor
+           (λ (filename #:wait? [wait? #f])
+             (set! edit-call (list filename wait?)))])
+       (dispatch-coreutils-command 'edit '--wait "one.txt"))
+     (check-equal? (path->string (first edit-call)) "one.txt")
+     (check-true (second edit-call))
+
+     (set! edit-call #f)
+     (parameterize
+         ([current-coreutils-editor
+           (λ (filename #:wait? [wait? #f])
+             (set! edit-call (list filename wait?)))])
+       (dispatch-coreutils-command 'edit "one.txt"))
+     (check-equal? (path->string (first edit-call)) "one.txt")
+     (check-false (second edit-call))
+
+     (check-exn
+      exn:fail?
+      (λ ()
+        (parameterize
+            ([current-coreutils-editor
+              (λ (filename #:wait? [wait? #f]) (void))])
+          (dispatch-coreutils-command 'edit "one.txt" "two.txt"))))
 
      (call-with-output-file "lines.txt"
        #:exists 'truncate
@@ -106,6 +135,27 @@
                    "one\ntwo\n")
      (check-equal? (capture-output coreutils-tail "-n" "1" "lines.txt")
                    "three\n")
+
+     ;; A long physical line must not force head or tail to materialize that
+     ;; line in memory. The 64 KiB internal block size is crossed many times.
+     (define long-lines-path (build-path test-root "long-lines.txt"))
+     (define long-chunk (make-bytes (* 64 1024) 120))
+     (call-with-output-file long-lines-path
+       #:exists 'truncate
+       (λ (out)
+         (display "first\n" out)
+         (for ([i (in-range 64)])
+           (write-bytes long-chunk out))
+         (display "\nlast-one\nlast-two\n" out)))
+     (check-equal? (capture-output coreutils-head "-n" "1" long-lines-path)
+                   "first\n")
+     (check-equal? (capture-output coreutils-tail "-n" "2" long-lines-path)
+                   "last-one\nlast-two\n")
+     (call-with-input-file long-lines-path
+       (λ (in)
+         (parameterize ([current-input-port in])
+           (check-equal? (capture-output coreutils-tail "-n" "2")
+                         "last-one\nlast-two\n"))))
      (check-equal? (capture-output coreutils-wc "-l" "lines.txt")
                    "3\n")
      (check-equal? (capture-output coreutils-basename "a/b/c.txt")
@@ -146,6 +196,23 @@
      (check-true (regexp-match? #px"[0-9]{4}-[0-9]{2}-[0-9]{2}T"
                                 (capture-output coreutils-date "--iso")))
 
+
+     ;; time writes measurements to stderr without contaminating command output.
+     (define time-error (open-output-string))
+     (define timed-output
+       (parameterize ([current-error-port time-error])
+         (capture-output
+          dispatch-coreutils-command
+          'time
+          'echo
+          'timed)))
+     (check-equal? timed-output "timed\n")
+     (define time-output (get-output-string time-error))
+     (check-true
+      (regexp-match?
+       #px"^real\\t[0-9]+[.][0-9]{3}s\ncpu\\t[0-9]+[.][0-9]{3}s\ngc\\t[0-9]+[.][0-9]{3}s\n$"
+       time-output))
+
      (check-exn
       exn:fail?
       (λ ()

tests/rash-smoke.rkt

@@ -2,6 +2,7 @@
 
 (require rackunit
          racket/file
+         racket/path
          racket/port
          rash-coreutils)
 
@@ -11,13 +12,17 @@
   (open-output-string))
 (define errors
   (open-output-string))
+(define edited #f)
 
 (dynamic-wind
  void
  (λ ()
    (parameterize ([current-directory test-root]
                   [current-output-port output]
-                  [current-error-port errors])
+                  [current-error-port errors]
+                  [current-coreutils-editor
+                   (λ (filename #:wait? [wait? #f])
+                     (set! edited (list filename wait?)))])
      {
       (call-with-output-file "info.rkt"
         #:exists 'truncate
@@ -30,21 +35,30 @@
       ls -l rash-coreutils-smoke
       ls *.rkt
       ls #px"^info[.]rkt$"
+      edit --wait info.rkt
 
       (define x 42)
       env RASH_COREUTILS_VALUE=(values x) printenv RASH_COREUTILS_VALUE
 
       echo one two three | wc -w
+      time echo timed
       date --iso
       rm -r rash-coreutils-smoke
 
       (check-false (directory-exists? "rash-coreutils-smoke"))
       })
-   (check-equal? (get-output-string errors) "")
+   (define error-text (get-output-string errors))
+   (check-true
+    (regexp-match?
+     #px"^real\\t[0-9]+[.][0-9]{3}s\ncpu\\t[0-9]+[.][0-9]{3}s\ngc\\t[0-9]+[.][0-9]{3}s\n$"
+     error-text))
    (define text (get-output-string output))
    (check-true (regexp-match? #rx"hello from rash-coreutils" text))
    (check-true (regexp-match? #rx"info[.]rkt" text))
    (check-true (regexp-match? #rx"42" text))
+   (check-true (regexp-match? #rx"timed" text))
+   (check-equal? (path->string (first edited)) "info.rkt")
+   (check-true (second edited))
    (check-true (regexp-match? #rx"\n3\n" text))
    (check-true (regexp-match? #px"[0-9]{4}-[0-9]{2}-[0-9]{2}T" text)))
  (λ ()