bash loging, startup scripts and shell initialization files..<\/p>\n
ok, i will talk about bash,<\/p>\n
When a user logs in, environment variables are set from various places.
\nstartup scripts in order is like this:<\/p>\n
some of this scripts may not exists in your system (~\/.bash_profile, ~\/.bash_login, ~\/.profile, ~\/.bashrc, \/etc\/bashrc and and ~\/.bash_logout),<\/p>\n
lets we explain them: 2. \/etc\/shadow 4. \/etc\/profile 5. \/etc\/profile.d\/*.sh 6. ~\/.bash_profile, ~\/.bash_login, and ~\/.profile * ~\/.bashrc finaly may be you would like to know that when you create a new user, then the home directory for that user will initialised with files from the \/etc\/skel directory (i.e \/etc\/skel directory contains subdirectories and files used to populate a new user’s home directory). The system administrator can create files in \/etc\/skel\/ directory that will provide a default environment for users. to understand them better (\/etc\/profile, ~\/.bash_profile, ~\/.bash_login, ~\/.profile, ~\/.bashrc, \/etc\/bashrc and and ~\/.bash_logout) this sites may give help: bash loging, startup scripts and shell initialization files.. ok, i will talk about bash, When a user logs in, environment variables are set from various places. startup scripts in order is like this: \/etc\/passwd \/etc\/shadow \/etc\/group \/etc\/profile will run. then all the files (that end with sh) in the \/etc\/profile.d directory then bash will look […]<\/p>\n","protected":false},"author":1,"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,"ngg_post_thumbnail":0,"footnotes":""},"categories":[14,7],"tags":[],"class_list":["post-11","post","type-post","status-publish","format-standard","hentry","category-bash","category-scripting-cli"],"_links":{"self":[{"href":"https:\/\/blog.sqawasmi.com\/index.php\/wp-json\/wp\/v2\/posts\/11","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blog.sqawasmi.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.sqawasmi.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.sqawasmi.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.sqawasmi.com\/index.php\/wp-json\/wp\/v2\/comments?post=11"}],"version-history":[{"count":0,"href":"https:\/\/blog.sqawasmi.com\/index.php\/wp-json\/wp\/v2\/posts\/11\/revisions"}],"wp:attachment":[{"href":"https:\/\/blog.sqawasmi.com\/index.php\/wp-json\/wp\/v2\/media?parent=11"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.sqawasmi.com\/index.php\/wp-json\/wp\/v2\/categories?post=11"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.sqawasmi.com\/index.php\/wp-json\/wp\/v2\/tags?post=11"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
\n
\n1. \/etc\/passwd
\n<\/span>\/etc\/passwd file contains basic user attributes. This is an ASCII file that contains an entry for each user. Each entry defines the basic attributes applied to a user.
\nAn entry in the \/etc\/passwd file has the following form (one entry per line):
\nName:Password:UserID:PrincipleGroup:Gecos:HomeDirectory:Shell
\nFor security reasons, most Linux Distributions no longer store password in this file (store it in \/etc\/shadow).
\nA corrupt \/etc\/passwd file can easily render a Linux box unusable.
\nfor more info about \/etc\/passwd see:
\nmanpages: man passwd<\/span><\/p>\n
\nshadow contains the encrypted password information for user’s accounts and optional the password aging information (other information such as account or password expiration values, etc).
\nfor more info:
\nmanpages: man shadow
\nhttp:\/\/db.assam-glug.org\/documentations\/Linux-admin-made-easy\/shadow-file-formats.html<\/span><\/a><\/span>
\n
\n3. \/etc\/group
\n\/etc\/group is an ASCII file which defines the groups to which users belong. There is one entry per line, and each line has the format:
\ngroup_name:passwd:GID:user1,user2,user3….userN
\nas you see, you have to sperate each user with comma.
\nfor more info see:
\nmanpages: man group<\/span><\/p>\n
\n\/etc\/profile file contains system wide environment stuff and startup programs, all settings that you want to apply to all your users environments should be in this file.<\/p>\n
\n\/etc\/profile.d is a good place to put application specific settings and their environment variables.<\/p>\n
\nthey can be used like \/etc\/profile file but for a specific user… they are user-specific bash environmental default settings, contains extra configuration options or change default settings.
\nbash will look for ~\/.bash_profile, ~\/.bash_login, and ~\/.profile, in that order, and reads and executes commands from the first one that exists and is readable.
\n~\/.profile is good when use another shell (like csh) that will not understand bash command and will look for this file.<\/p>\n
\nthis file used for user-specific aliases, export and user functions.
\n~\/.bashrc might point to \/etc\/bashrc to run global things.<\/p>\n
\ni dont know a good site talking about that, but take a look at this one:
\nhttp:\/\/www.faqs.org\/docs\/linux_admin\/x2331.html<\/a><\/span><\/p>\n
\nhttp:\/\/www.faqs.org\/docs\/abs\/HTML\/files.html<\/a>
\nhttp:\/\/www.faqs.org\/docs\/securing\/chap6sec64.html<\/a>
\nhttp:\/\/tldp.org\/LDP\/Bash-Beginners-Guide\/html\/sect_03_01.html<\/a>
\nhttp:\/\/www.linux-migration.org\/ch02s03.html<\/a>
\nhttp:\/\/www.gnu.org\/software\/bash\/manual\/bash.html<\/a>
\nhttp:\/\/www.comptechdoc.org\/os\/linux\/usersguide\/linux_ugenvironment.html<\/a>
\nhttp:\/\/www.linuxfromscratch.org\/blfs\/view\/6.1\/postlfs\/profile.html<\/a><\/span><\/p>\nRelated Images:<\/h3>","protected":false},"excerpt":{"rendered":"