{"id":42643,"date":"2019-05-24T16:06:31","date_gmt":"2019-05-24T14:06:31","guid":{"rendered":"https:\/\/mamchenkov.net\/wordpress\/?p=42643"},"modified":"2019-05-24T16:09:20","modified_gmt":"2019-05-24T14:09:20","slug":"falsehoods-programmers-believe-about-unix-time","status":"publish","type":"post","link":"https:\/\/mamchenkov.net\/wordpress\/2019\/05\/24\/falsehoods-programmers-believe-about-unix-time\/","title":{"rendered":"Falsehoods programmers believe about Unix time"},"content":{"rendered":"\n\n
\"\"<\/figure><\/div>\n\n\n\n

A while back I blogged a collection of “Falsehoods programmers believe about …<\/a>“. One of those things was time. Today I came across a nice addition to that – “Falsehoods programmers believe about Unix time<\/a>“.<\/p>\n\n\n\n

These three facts all seem eminently sensible and reasonable, right?
1. Unix time is the number of seconds since 1 January 1970 00:00:00 UTC
2. If I wait exactly one second, Unix time advances by exactly one second
3. Unix time can never go backwards
False, false, false.<\/p><\/blockquote>\n\n\n\n

All three of these are false and for the same reason – leap seconds. The article provides a nice and easy explanation of how and why that happens.<\/p>\n\n","protected":false},"excerpt":{"rendered":"\n

A while back I blogged a collection of “Falsehoods programmers believe about …“. One of those things was time. Today I came across a nice addition to that – “Falsehoods programmers believe about Unix time“. These three facts all seem eminently sensible and reasonable, right?1. Unix time is the number of seconds since 1 January … Continue reading Falsehoods programmers believe about Unix time<\/span><\/a><\/p>\n\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"Falsehoods programmers believe about Unix time #WebDev #UNIX #Linux #time ","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2},"_links_to":"","_links_to_target":""},"categories":[1,6,18,62,1334],"tags":[253,1330],"keyring_services":[],"class_list":["post-42643","post","type-post","status-publish","format-standard","hentry","category-general","category-linux","category-programming","category-technology","category-web-work","tag-unix","tag-web-development"],"aioseo_notices":[],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack-related-posts":[{"id":25949,"url":"https:\/\/mamchenkov.net\/wordpress\/2016\/03\/16\/falsehoods-programmers-believe-about\/","url_meta":{"origin":42643,"position":0},"title":"Falsehoods programmers believe about …","author":"Leonid Mamchenkov","date":"March 16, 2016","format":false,"excerpt":"I thought I've posted some of these links a while back but alas I can't find them in the archives. \u00a0Maybe I just thought I did. \u00a0So here they go with some new additions: Falsehoods Programmers Believe About Names Falsehoods Programmers Believe About\u00a0Time Falsehoods Programmers Believe About\u00a0Addresses Falsehoods Programmers Believe\u2026","rel":"","context":"In "All"","block_context":{"text":"All","link":"https:\/\/mamchenkov.net\/wordpress\/category\/general\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":31955,"url":"https:\/\/mamchenkov.net\/wordpress\/2019\/02\/05\/dotfile-madness\/","url_meta":{"origin":42643,"position":1},"title":"Dotfile madness","author":"Leonid Mamchenkov","date":"February 5, 2019","format":false,"excerpt":"\"Dotfile madness\" is an excellent look at the problem of hidden data and configuration files that seem to be multiplying lately in the users' home directories: We are no longer in control of our home directories.My own home directory contains 25 ordinary files and 144 hidden files. 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