Release Notes: busybox-w32 FRP-3902-g61e53aa93 (2021-03-03)

Release Notes

busybox-w32 version FRP-3902-g61e53aa93 was released on 2021-03-03. It is the current release. For other release notes see:

Symbolic links

Creation of symbolic links is now supported. Microsoft Windows doesn't, by default, allow ordinary users to create symbolic links so despite this change things may still not work for you.

To create symbolic links you must either:

Run busybox-w32 with elevated privileges ('as Administrator'). The su applet may help with this.
Edit security policy to give users the 'Create symbolic links' privilege. Unfortunately this doesn't work for users who are an Administrator.
Enable developer mode, which is available in later versions of Windows 10.

Even with these preconditions creation of symbolic links may still fail if your version of Windows or file system doesn't support this feature.

The command busybox --install -s can be used to install symbolic links for all of the applets in BusyBox. Without the -s hard links are created instead.

The command busybox --uninstall still only works for hard links.

ANSI escape sequences

A number of improvements have been made to the treatment of ANSI escape sequences, especially in relation to colour handling.

The printf applet was modified in the FRP-3532 release to allow ANSI escape sequences to work in certain circumstances. Further changes have been made so that escape sequences should work for almost any string output by a single invocation of printf.
ANSI emulation has been extended to include:
```
   ESC[38;2;R;G;Bm   24-bit foreground colour
   ESC[48;2;R;G;Bm   24-bit background colour
   ESC[38;5;Nm        8-bit foreground colour
   ESC[48;5;Nm        8-bit background colour
```
The full range of colours is only available in terminals that have native support for ANSI escapes. In old-style Windows consoles colours are mapped to the closest available value.
Since FRP-3466 the environment variable setting BB_SKIP_ANSI_EMULATION=2 indicates that busybox-w32 should attempt to detect if the terminal has native support for escape sequences and use them if it does. This value is now the default. To force the use of emulation set BB_SKIP_ANSI_EMULATION=0; to force the use of actual escape sequences set BB_SKIP_ANSI_EMULATION=1.

New applets

The following applets have been enabled in the default configuration:

bc is an arbitrary precision calculator language with a syntax similar to C. This is the main reason the binaries are so much bigger.
nproc prints the number of available CPUs. This implementation supports a maximum of 64 CPUs.
free displays the amount of memory in use and pagefile (swap) usage. The values may not be directly comparable with those shown on a Unix system.
uptime displays the current time and how long the system has been up. On Unix it also displays the system load average but Windows doesn't collect this information.

Bug fixes

Renaming symbolic links and the deletion of symbolic links to directories should now work correctly.
Several features that weren't previously available in Windows 7 have been enabled. This is related to GitHub issue #204.
Support for compiling busybox-w32 using MSYS2 and mingw-w64 on Windows has been updated and brief instructions added to the README.

Changes imported from upstream

busybox-w32 has been synchronised with upstream BusyBox. As a result the following bug fixes and enhancements are available (among others):

printf('%c') in awk allows output of the NUL character.
In vi selection of ranges for change/delete/yank by forward character motion commands (SPACE or 'l') now allows the number of characters to be specified.
The line numbering command nl -b n outputs lines without numbers where previously it output lines without numbers and without any content.
The --help option works on certain applets (e.g. usleep) where it was previously broken.