Release Notes

busybox-w32 version FRP-5181-g5c1a3b00e was released on 2023-08-18. It is the current release. For other release notes see:

• the release before this one
• index of all release notes

Unicode support

Support for Unicode in Windows normally requires the use of the wide-character (W) API whereas busybox-w32 generally uses the narrow-character (A) API. Recent versions of Windows allow applications to include a manifest that permits the narrow API to handle UTF-8. This feature has been used to build a binary (busybox64u.exe) with improved support for Unicode.

Some things to note:

• This is the first public release of busybox-w32 with Unicode support: it should be used with caution.
• The necessary manifest is only supported on Windows 10 since release 1903 and Windows 11. The binary will fail to run on platforms where the required support isn't available.
• It has been necessary to apply workarounds for deficiencies in Microsoft's current support for UTF-8. There may be undiscovered problems and the workarounds themselves may have issues.
• Only a 64-bit binary has been provided.

As to actually using the binary:

• It isn't necessary to adjust the console code page.
• Unicode arguments to BusyBox applets or external utilities should work correctly.
• Unicode output from BusyBox applets is UTF-8.
• Literal unicode strings in scripts should be UTF-8.
• Interactive Unicode input and editing at the shell prompt is limited:
  • The Windows Terminal works better than the Windows console.
  • Typing or pasting Unicode should work correctly.
  • Editing (cursor movement, delete, etc) can be buggy, especially with double-width or combining characters.
• The presence of Unicode support is indicated in the busybox-w32 help output:

  ~ $ busybox | head -2
  BusyBox v1.37.0-FRP-5181-g5c1a3b00e (2023-08-18 12:18:42 BST)
  (mingw64-gcc 12.2.1-8.fc38; mingw64-crt 10.0.0-4.fc38; glob; Unicode)
  

Unicode support is largely the work of Avi Halachmi (@avih on GitHub), to whom all praise should be addressed. (Complaints, blame and other invective should fall to me, as usual ;-)

Overriding applets

The shell variable BB_OVERRIDE_APPLETS was introduced in release FRP-4716 as a way to replace internal applets with external commands. This release extends the feature:

• Applet names in the list can be separated by spaces, commas or semicolons.
• Applets before the first semicolon are disabled unconditionally. This matches the previous behaviour.
• Applets after the first semicolon are overridden if a matching external command exists but continue in use if one does not.
• '-' alone disables all applets.
• '+' alone overrides every applet for which a matching external command exists.

This setting:

    export BB_OVERRIDE_APPLETS=";make"

results in the internal make applet being used only if no external make binary is present on PATH.

(GitHub issue #329)

Shell options

There have been some changes to Windows-specific shell options.

The winxp option affects the import of environment variables by the shell. Since Windows XP is particularly fussy about the presence of backslashes in environment variables the winxp option was added to prevent backslashes from being converted into forward slashes on import.

• Previously winxp could only be set with the -X command line option, which had be the first provided. These restrictions have been lifted: winxp can be altered from within a shell with the set built-in and -X no longer has be the first item on the command line.
• Changing winxp within a shell will switch between forward slashes and backslashes in shell variables, but only in those variables which were imported from a native Windows environment. This requires the shell to track the origin of its variables. This tracking persists in a subshell but not when the variables are exported back to the environment of a new process.
• Although the option name references Windows XP it can be used in any version of Windows.

The noconsole option tries to hide the console window that appears when a busybox-w32 shell is run from a GUI application.

• Previously noconsole could only be set on the shell command line; it can now be set (or unset) within a shell with the set -o noconsole and set +o noconsole commands.
• When noconsole is set the shell is minimised rather than hidden.

(GitHub issues #322, #325)

Hidden system files

The ls applet follows both Unix and Windows conventions for hidden files:

• In Unix files with names starting with a dot are hidden.
• In Windows files with the 'hidden' file attribute are hidden.

Hidden files are normally not displayed but can be shown with ls -a or ls -A.

Some hidden files on Windows also have the 'system' attribute set. These are likely to be of little interest to users and many of them have ugly, long names. The display of such 'hidden system' files can be disabled by giving the -a or -A options more than once. For example, as ls -a -a or ls -AA.

Since duplicate options are ignored in other implementations of ls this idiom is portable.

(GitHub issue #328)

Bug fixes and enhancements

• It should now be possible to input double-byte characters in CJK codepages (932 and 936, for example). This has been broken since FRP-2962. (GitHub issue #335)
• The directory examples/mswin-build in the source tree contains scripts to replicate how release and pre-release binary are cross-compiled. (GitHub issue #330)
• Some files in ~/AppData/Local/Microsoft/WindowsApps are a special type of reparse point which wasn't properly handled by busybox-w32. They're now treated as a form of symbolic link by most applets. lsattr displays them with the A attribute:

  ~/AppData/Local/Microsoft/WindowsApps $ lsattr python.exe
  A-------a-- python.exe
  

  (GitHub issue #327)
• The date applet now supports the -s option to set the system time. This requires elevated privileges.
• Changes to diff in release FRP-4882 gave incorrect results when files with CRLF line-endings were compared and the --binary option wasn't used. This has been fixed, though there are still inconsistencies when files with different line-endings are compared. (GitHub issue #348)
• The previous release notes reported that upstream BusyBox had introduced improved support for the jobs and trap shell built-ins. Unfortunately, busybox-w32 users were unable to benefit from these changes due to deficiencies in the shell. These have been addressed so jobs and trap can now be used in the context of command substitution, process substitution and pipelines. (GitHub issue #350)

Changes imported from upstream

busybox-w32 has been synchronised with upstream BusyBox. There have been numerous bug fixes and enhancements, particularly in awk and support for maths in the shell.