htop

{{Short description|Command line system monitor}}

{{For|the homotopy category of topological spaces|hTop}}

{{Lowercase title}}

{{Infobox software

| name = htop

| screenshot = 250px

| author = Hisham Muhammad

| developer = Hisham Muhammad (2004–2019)
htop developer team (2020–present)

| released = {{Start date and age|2004|05}}{{Cite web|url=https://github.com/htop-dev/htop|title=GitHub - htop-dev/htop at 80f344559bba331d6daa2c913005e7eefddcf075|website=GitHub}}

| latest release version = {{wikidata|property|preferred|references|edit|Q1940220|P348|P548=Q2804309}}

| latest release date = {{wikidata|qualifier|preferred|single|Q1940220|P348|P548=Q2804309|P577}}

| latest preview version = {{wikidata|property|preferred|references|edit|Q1940220|P348|P548=Q51930650}}

| latest preview date = {{wikidata|qualifier|preferred|single|Q1940220|P348|P548=Q51930650|P577}}

| programming language = C (ncurses library)

| operating system = Linux, macOS, FreeBSD, OpenBSD, Solaris, Illumos, OpenIndiana

| genre = Process Viewer / System monitor

| license = GPL-2.0-or-later

| website = {{URL|https://htop.dev/}}

}}

htop is an interactive system monitor process viewer and process manager. It is designed as an alternative to the Unix program top.

It shows a frequently updated list of the processes running on a computer, normally ordered by the amount of CPU usage. Unlike top, htop provides a full list of processes running, instead of the top resource-consuming processes. htop uses color and gives visual information about processor, swap and memory status. htop can also display the processes as a tree.

Users often deploy htop in cases where Unix top does not provide enough information about the system's processes. htop is also popularly used interactively as a system monitor.{{cite web|url=https://community.rackspace.com/products/f/public-cloud-forum/6756/system-monitoring-with-htop|title=System Monitoring with htop|access-date=2018-02-05|archive-url=https://web.archive.org/web/20180618152249/https://community.rackspace.com/products/f/public-cloud-forum/6756/system-monitoring-with-htop|archive-date=2018-06-18|url-status=dead}} Compared to top, it provides a more convenient, visual, cursor-controlled interface for sending signals to processes.

htop is written in the C programming language using the ncurses library. Its name is derived from the original author's first name, as a nod to pinfo,{{Cite web |title=Pinfo - A lynx-style info and man reader |url=http://pinfo.sourceforge.net |url-status=deviated |archive-url=https://web.archive.org/web/20150402074958/http://pinfo.sourceforge.net/ |archive-date=April 2, 2015 |access-date=November 24, 2014}} an info-replacement program that does the same.{{cite web |title=htop FAQ |url=http://hisham.hm/htop/index.php?page=faq |archive-url=https://web.archive.org/web/20140121201425/http://hisham.hm/htop/index.php?page=faq |archive-date=January 21, 2014 |access-date=2012-06-15}}

Because system monitoring interfaces are not standardized among Unix-like operating systems, much of htop's code must be rewritten for each operating system. Cross-platform, OpenBSD, FreeBSD and OS X (now macOS) support was added in htop 2.0.{{cite web|url=https://www.youtube.com/watch?v=g5GamptmWeA |archive-url=https://ghostarchive.org/varchive/youtube/20211221/g5GamptmWeA |archive-date=2021-12-21 |url-status=live|title=Going cross-platform: how htop was made portable - FOSDEM 2016|website=YouTube|date=10 February 2016 |accessdate=2016-12-30}}{{cbignore}}{{Cite web |title=Htop - an interactive process viewer |url=http://hisham.hm/htop/index.php?page=downloads |archive-url=https://web.archive.org/web/20180927125349/http://hisham.hm/htop/index.php?page=downloads |archive-date=September 27, 2018 |access-date=September 27, 2018}} Solaris/Illumos/OpenIndiana support was added in 2.2.0.

htop was forked by several developers as htop-dev,{{Cite web |title=Htop forked to htop-dev, version 3.0.0 released with over 2 years of bug fixes and features {{!}} Lobsters |url=https://lobste.rs/s/r2rxg9/htop_forked_htop_dev_version_3_0_0_released |access-date=2024-10-04 |website=lobste.rs}} and with support from the original author, the homepage was later redirected to a new domain.{{Cite web|url=https://hisham.hm/htop/|title=hisham.hm/htop|website=Hisham Muhammad|access-date=2020-12-08}}