Introduction

lspac is a helper tool for pacman, built using the libalpm library. It's main purpose is to fetch information about packages from pacman and print it to the stdout in a way that it's friendly for parsing, so it facilitates the creation of scripts that deals with pacman package information.

Installation

To install lspac simply follow one of the methods below:

AUR

Using the AUR

yay -S lspac

or

git clone https://aur.archlinux.org/lspac
cd lspac
makepkg -si

Manual

Manual installation

git clone https://github.com/pvpscript/lspac
cd lspac
make
sudo make install

Usage

lspac [OPTIONS] [<PACKAGE> ...]

Options

-c, --pacman-conf PATH

Set the pacman config file (default '/etc/pacman.conf').

-d, --dbpath PATH

Set pacman dbpath.

-r, --root PATH

Set the filesystem root dir.

-f, --field-delim CHAR

Set the field used between each selected output field (default: tab).

-i, --inner-delim CHAR

Set the inner values delimiter (default: space).

-p, --pkg-delim CHAR

Set the delimiter used between each prompted package.

-o, --output LIST

Set the output fields list (for more information, refer to lspac --help).

-s, --surround CHAR

Set the character used to surround each output value (default: double quotes).

-t, --tarball PATH

Fetches data from a given package tarball.

-S, --select-db DATABASE

Select between local database and sync databases (default: both).

-b, --bytes

Display package size as bytes, instead of human readable.

-P, --pairs

Show outputs in a KEY="VALUE" fashion.

-u, --unix

Display dates as unix timestamp, instead of human readable.

-w, --raw

Remove surrounding characters (overwrites -s).

-B, --basic

Show basic informations about a package. Same as -o PROVIDES,DEPENDS,REQUIREDBY,OPTIONALFOR,CONFLICTS,REPLACES,CHECKDEPENDS,MAKEDEPENDS

-R, --relations

Show the relations of a given package. Same as -o DBNAME,BASENAME,VERSION,DESC,ARCH,URL,PACKAGER,SIZE,BUILDDATE,INSTALLDATE

-O, --output-all

Shows every single available output value.

-h, --help

Shows help menu.

-v, --version

Displays version.

Manual page

For extra help and information about this tool's usage, refer to the lspac(1) manual page.

Reference

This project was strongly inspired by lsblk, a tool from util-linux that lists block devices. By reading its code, I was able to absorb enough information in how a proper input parsing is done, as well as the clever enum + struct array solution for associating numerical values with strings and their respective information. I really recommend taking a look at the code, it's very concise and very well written; a delightful experience to the eyes and mind of every programmer.

The library used was the pacman libalpm which is provided with the core pacman package. It's source code can be found here. Note that there's still no manual page for this library, as they claim it is still under construction, but the header file might be able to provide enough information for some development.

Another important project that helped a lot in the development of this tool, was pacutils, which, by reading their code I've got enough insight to how the libalpm worked.