{"id":29107,"date":"2018-12-18T15:58:01","date_gmt":"2018-12-18T13:58:01","guid":{"rendered":"https:\/\/mamchenkov.net\/wordpress\/?p=29107"},"modified":"2018-12-18T15:58:09","modified_gmt":"2018-12-18T13:58:09","slug":"bash-parameter-expansion","status":"publish","type":"post","link":"https:\/\/mamchenkov.net\/wordpress\/2018\/12\/18\/bash-parameter-expansion\/","title":{"rendered":"Bash parameter expansion"},"content":{"rendered":"<!-- google_ad_section_start -->\n\n<p class=\"wp-block-paragraph\">If you&#8217;ve ever written a bash script with variables, and know that it wasn&#8217;t your last one,\u00a0 I promise you, you&#8217;ll love <a href=\"http:\/\/wiki.bash-hackers.org\/syntax\/pe\">this wiki page<\/a>.\u00a0 It covers a whole lot of different ways to expand and manipulate variable values in bash, all on a single, conveniently organized page.<\/p>\n<!-- google_ad_section_end -->\n","protected":false},"excerpt":{"rendered":"<!-- google_ad_section_start -->\n<p>If you&#8217;ve ever written a bash script with variables, and know that it wasn&#8217;t your last one,\u00a0 I promise you, you&#8217;ll love this wiki page.\u00a0 It covers a whole lot of different ways to expand and manipulate variable values in bash, all on a single, conveniently organized page.<\/p>\n<!-- google_ad_section_end -->\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_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_feature_clip_id":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"Bash parameter expansion #bash #CLI","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},"jetpack_post_was_ever_published":false,"_links_to":"","_links_to_target":""},"categories":[1,6,18,133,62],"tags":[3098,1960],"keyring_services":[],"class_list":["post-29107","post","type-post","status-publish","format-standard","hentry","category-general","category-linux","category-programming","category-sysadmin","category-technology","tag-bash","tag-command-line"],"aioseo_notices":[],"aioseo_head":"\n\t\t<!-- All in One SEO 4.9.8 - aioseo.com -->\n\t<meta name=\"description\" content=\"If you&#039;ve ever written a bash script with variables, and know that it wasn&#039;t your last one, I promise you, you&#039;ll love this wiki page. 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The wrong way to go about this is: #!\/bin\/bash for FILE in $* do echo \"$FILE\"\u2026","rel":"","context":"In &quot;All&quot;","block_context":{"text":"All","link":"https:\/\/mamchenkov.net\/wordpress\/category\/general\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":28622,"url":"https:\/\/mamchenkov.net\/wordpress\/2018\/06\/11\/safe-ways-to-do-things-in-bash\/","url_meta":{"origin":29107,"position":2},"title":"Safe ways to do things in bash","author":"Leonid Mamchenkov","date":"June 11, 2018","format":false,"excerpt":"\"Safe ways to do things in bash\" is yet another guide to some of the best practices for writing bash scripts.\u00a0 It covers all the usual bits of quoting, escaping, error handling, and more.","rel":"","context":"In &quot;All&quot;","block_context":{"text":"All","link":"https:\/\/mamchenkov.net\/wordpress\/category\/general\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":10202,"url":"https:\/\/mamchenkov.net\/wordpress\/2006\/06\/22\/bash-shortcuts\/","url_meta":{"origin":29107,"position":3},"title":"Bash shortcuts","author":"Leonid Mamchenkov","date":"June 22, 2006","format":false,"excerpt":"While reading about Joe Grossberg's making it in the Mac world, I noticed the \"ALT-.\" bash shortcut (he mentions it in his post). the fact that doing ALT-. at the bash command-line doesn't behave normally. Instead of repeating the last argument of the previous command, it outputs some characters. That\u2026","rel":"","context":"In &quot;All&quot;","block_context":{"text":"All","link":"https:\/\/mamchenkov.net\/wordpress\/category\/general\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":23357,"url":"https:\/\/mamchenkov.net\/wordpress\/2015\/01\/21\/shellfire-bash-sh-dash-function-libraries\/","url_meta":{"origin":29107,"position":4},"title":"shellfire &#8211; namespaced, composable shell (bash, sh and dash) function libraries","author":"Leonid Mamchenkov","date":"January 21, 2015","format":"link","excerpt":"shellfire - namespaced, composable shell (bash, sh and dash) function libraries","rel":"","context":"In &quot;All&quot;","block_context":{"text":"All","link":"https:\/\/mamchenkov.net\/wordpress\/category\/general\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":27291,"url":"https:\/\/mamchenkov.net\/wordpress\/2017\/02\/05\/defensive-bash-programming\/","url_meta":{"origin":29107,"position":5},"title":"Defensive BASH Programming","author":"Leonid Mamchenkov","date":"February 5, 2017","format":false,"excerpt":"If you write any Bash code that lasts more than a day, you should definitely read \"Defensive BASH Programming\" and follow the advice, if you haven't already. \u00a0It covers the following: Immutable global variables Everything is local main() Everything is a function Debugging functions Code clarity Each line does just\u2026","rel":"","context":"In &quot;All&quot;","block_context":{"text":"All","link":"https:\/\/mamchenkov.net\/wordpress\/category\/general\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]}],"jetpack_sharing_enabled":true,"amp_enabled":true,"_links":{"self":[{"href":"https:\/\/mamchenkov.net\/wordpress\/wp-json\/wp\/v2\/posts\/29107","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mamchenkov.net\/wordpress\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mamchenkov.net\/wordpress\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mamchenkov.net\/wordpress\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/mamchenkov.net\/wordpress\/wp-json\/wp\/v2\/comments?post=29107"}],"version-history":[{"count":0,"href":"https:\/\/mamchenkov.net\/wordpress\/wp-json\/wp\/v2\/posts\/29107\/revisions"}],"wp:attachment":[{"href":"https:\/\/mamchenkov.net\/wordpress\/wp-json\/wp\/v2\/media?parent=29107"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mamchenkov.net\/wordpress\/wp-json\/wp\/v2\/categories?post=29107"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mamchenkov.net\/wordpress\/wp-json\/wp\/v2\/tags?post=29107"},{"taxonomy":"keyring_services","embeddable":true,"href":"https:\/\/mamchenkov.net\/wordpress\/wp-json\/wp\/v2\/keyring_services?post=29107"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}