pacman-alternatives

A utility for managing symbolic links (alternatives) of pacman packages.

Installation

git clone https://github.com/termux-pacman/pacman-alternatives.git
cd pacman-alternatives

# on pacman-based Termux
make

# on pacman-based Linux distributions
sudo make

Variables for installation configuration:

Variable	Type	Description	Default
DEF_OS	android/linux	host operating system	automatically detects host OS
PREFIX	absolute path	main path for installing and routing system files	on Linux - /usr, on Android (Termux) - /data/data/com.termux/files/usr
DESTDIR	empty/path	path to installing temporary directory	empty
SYSDIR	absolute path	main path for routing alternative (links and root files) paths	on Linux - /, on Android (Termux) - /data/data/com.termux/files/usr/
LINKDIR	empty/absolute path	path for routing links of alternatives	empty
ROOTDIR	empty/absolute path	path for routing root files of alternatives	empty
ALTER_FILES_PATH	relative path/absolute path	path to directory for alternative files	share/pacman-alternatives
ENABLED_ALTERS_PATH	relative path/absolute path	path to directory for active alternatives	var/lib/pacman/alternatives
READER_USER	username/empty	user for reading alternative files	on Linux - pacman-alternatives, on Android (Termux) - empty (disabling use of reader user)
BINDIR	absolute path	path to bin/	$(PREFIX)/bin
BASHPATH	absolute path	path to bash	$(BINDIR)/bash
ALPMDIR	absolute path	path to ALPM directory	$(PREFIX)/share/libalpm
ALPM_HOOK_DIR	absolute path	path to hooks directory of ALPM	$(ALPMDIR)/hooks
ALPM_SCRIPT_DIR	absolute path	path to scripts directory of ALPM	$(ALPMDIR)/scripts

Operations

Name	Flag	Description
Disable	-D/--disable	Disable enabled alternative(s)
Enable	-E/--enable	Enable available (disabled) alternative(s)
Install	-I/--install	Install alternative file(s) into system
Query	-Q/--query	Output of information about alternative(s), checking alternative(s)
Reject	-R/--reject	Reject selected alternative(s)
Select	-S/--select	Select enabled alternative(s)
Uninstall	-U/--uninstall	Uninstall alternative file(s) from system

Example of use

Installing nano (editor:nano) alternative file:

pacman-alternatives -I ./nano.alt

Enabling editor:nano alternative and selecting it in auto mode:

pacman-alternatives -Ea nano

Summary of enabled alternatives by editor alternative group:

pacman-alternatives -Q editor:

Selecting alternative by editor alternative group in manual mode:

pacman-alternatives -S editor:

Rejecting selected alternative in editor alternative group and replacing it:

pacman-alternatives -Rr editor:

Disabling and rejecting editor:nano alternative without confirmation:

pacman-alternatives -Dr :nano --noconfirm

Uninstalling nano (editor:nano) alternative from system without confirmation:

pacman-alternatives -U nano --noconfirm

Checking all enabled alternatives:

pacman-alternatives -Qc

System variables

Variable	Type	Description
PA_RUN_IN_ALPM_HOOKS	bool	configure output and processing for the ALPM environment
PA_VERBOSE	bool	enable verbose mode
PA_SYSDIR	absolute path	set path for routing alternative (links and root files) paths (must begin and end with /)
PA_ROOTDIR	empty/absolute path	set path for routing root files of alternatives (must begin and end with /)
PA_LINKDIR	empty/absolute path	set path for routing links of alternatives (must begin and end with /)
PA_PREFIX	absolute path	set path for routing system files
PA_ALTER_FILES_PATH	relative path/absolute path	set path to directory for alternative files (if relative path is specified, absolute path is formed using _pa_prefix: "${_pa_prefix}/${PA_ALTER_FILES_PATH}")
PA_ENABLED_ALTERS_PATH	relative path/absolute path	set path to directory for active alternatives (if relative path is specified, absolute path is formed using _pa_prefix: "${_pa_prefix}/${PA_ENABLED_ALTERS_PATH}")
PA_READER_USER	username/empty	set reader username (if empty, the use of reader user is disabled)

Syntax file alternative

File alternative is a shell script in the .alt format, which stores alter_group_* functions that allow flexibly configuring alternatives and easily collecting alternative metadata from them (group:name:priority:link:root).

Syntax rules:

• Alternative name and alternative group name can consist of letters, numbers and the special characters -/_.
• Paths in the sysdir, linkdir and rootdir variables must begin and end with the / character.
• Value of priority variable must be integer.
• Paths specified in the associations variable must be relative.

# example file alternative `example.alt`

priority=10
sysdir="/usr/local/"

alter_group_group1() {
    associations=(
        bin/link1_1:bin/root1_1
        bin/link1_2:bin/root1_2
    )
    # final metadata:
    # - group1:example:10:/usr/local/bin/link1_1:/usr/local/bin/root1_1
    # - group1:example:10:/usr/local/bin/link1_2:/usr/local/bin/root1_2
}

alter_group_group2() {
    sysdir+="bin/"
    associations=(link2:root2)
    # final metadata:
    # - group2:example:10:/usr/local/bin/link2:/usr/local/bin/root2
}

function alter_group_group3 {
    priority=20
    linkdir="/usr/"
    rootdir="/usr/local/"
    associations=(bin/link3:sbin/root3)
    # final metadata:
    # - group3:example:20:/usr/bin/link3:/usr/local/sbin/root3
}