Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression

/
/
gm

Test String

Substitution

Processing...

Code Generator

Generated Code

# If you'd like to omit non-matching lines from the result; add ';d' to the end of the expression. sed -E 's/\$([^{("\\'\\/])([a-zA-Z0-9_]*)([^}\\/ \t'"\n.\]:(=\\-]*)/${$1$2$3}/gm;t' <<< "amavis_permissions_status=$(find -H $amavis_state_dir -maxdepth 3 -a \( \! -user amavis -o \! -group amavis \)) if [[ -n $amavis_permissions_status ]] then _notify 'inf' \"Fixing $amavis_state_dir permissions\" chown -hR amavis:amavis $amavis_state_dir else _notify 'inf' \"Permissions in $amavis_state_dir look OK\" return 0 fi } function _fix_cleanup_clamav() { _notify 'task' 'Cleaning up disabled Clamav' rm -f /etc/logrotate.d/clamav-* rm -f /etc/cron.d/clamav-freshclam } function _fix_cleanup_spamassassin() { _notify 'task' 'Cleaning up disabled spamassassin' rm -f /etc/cron.daily/spamassassin } ########################################################################## # << Fix Stack ########################################################################## ########################################################################## # >> Misc Stack # # Description: Place functions that do not fit in the sections above here ########################################################################## function misc() { _notify 'taskgrp' 'Starting Misc' for _func in \"${FUNCS_MISC[@]}\" do if ! $_func then _defunc fi done } function _misc_save_states() { # consolidate all states into a single directory (`/var/mail-state`) to allow persistence using docker volumes statedir=/var/mail-state if [[ $ONE_DIR -eq 1 ]] && [[ -d $statedir ]] then _notify 'inf' \"Consolidating all state onto $statedir\" local FILES=( /var/spool/postfix /var/lib/postfix /var/lib/amavis /var/lib/clamav /var/lib/spamassassin /var/lib/fail2ban /var/lib/postgrey /var/lib/dovecot ) for d in \"${FILES[@]}\" do dest=\"$statedir/$(echo \"$d\" | sed -e 's/.var.//; s/\//-/g')\" if [[ -d $dest ]] then _notify 'inf' \" Destination $dest exists, linking $d to it\" rm -rf \"$d\" ln -s \"$dest\" \"$d\" elif [[ -d $d ]] then _notify 'inf' \" Moving contents of $d to $dest:\" \"$(ls \"$d\")\" mv \"$d\" \"$dest\" ln -s \"$dest\" \"$d\" else _notify 'inf' \" Linking $d to $dest\" mkdir -p \"$dest\" ln -s \"$dest\" \"$d\" fi done _notify 'inf' 'Fixing /var/mail-state/* permissions' chown -R clamav /var/mail-state/lib-clamav chown -R postfix /var/mail-state/lib-postfix chown -R postgrey /var/mail-state/lib-postgrey chown -R debian-spamd /var/mail-state/lib-spamassassin chown -R postfix /var/mail-state/spool-postfix fi } ########################################################################## # >> Start Daemons ########################################################################## function start_daemons() { _notify 'taskgrp' 'Starting mail server' for _func in \"${DAEMONS_START[@]}\" do if ! $_func then _defunc fi done } function _start_daemons_cron() { _notify 'task' 'Starting cron' 'n' supervisorctl start cron } function _start_daemons_rsyslog() { _notify 'task' 'Starting rsyslog ' 'n' supervisorctl start rsyslog } function _start_daemons_saslauthd() { _notify 'task' 'Starting saslauthd' 'n' supervisorctl start \"saslauthd_${SASLAUTHD_MECHANISMS}\" } function _start_daemons_fail2ban() { _notify 'task' 'Starting fail2ban ' 'n' touch /var/log/auth.log # delete fail2ban.sock that probably was left here after container restart if [[ -e /var/run/fail2ban/fail2ban.sock ]] then rm /var/run/fail2ban/fail2ban.sock fi supervisorctl start fail2ban } function _start_daemons_opendkim() { _notify 'task' 'Starting opendkim ' 'n' supervisorctl start opendkim } function _start_daemons_opendmarc() { _notify 'task' 'Starting opendmarc ' 'n' supervisorctl start opendmarc } function _start_daemons_postsrsd() { _notify 'task' 'Starting postsrsd ' 'n' supervisorctl start postsrsd } function _start_daemons_postfix() { _notify 'task' 'Starting postfix' 'n' supervisorctl start postfix } function _start_daemons_dovecot() { # Here we are starting sasl and imap, not pop3 because it's disabled by default _notify 'task' 'Starting dovecot services' 'n' if [[ $ENABLE_POP3 -eq 1 ]] then _notify 'task' 'Starting pop3 services' 'n' mv /etc/dovecot/protocols.d/pop3d.protocol.disab /etc/dovecot/protocols.d/pop3d.protocol fi if [[ -f /tmp/docker-mailserver/dovecot.cf ]] then cp /tmp/docker-mailserver/dovecot.cf /etc/dovecot/local.conf fi supervisorctl start dovecot # TODO fix: on integration test # doveadm: Error: userdb lookup: connect(/var/run/dovecot/auth-userdb) failed: No such file or directory # doveadm: Fatal: user listing failed # if [[ $ENABLE_LDAP -ne 1 ]] # then # echo \"Listing users\" # /usr/sbin/dovecot user '*' # fi } function _start_daemons_fetchmail() { _notify 'task' 'Starting fetchmail' 'n' /usr/local/bin/setup-fetchmail supervisorctl start fetchmail } function _start_daemons_clamav() { _notify 'task' 'Starting clamav' 'n' supervisorctl start clamav } function _start_daemons_postgrey() { _notify 'task' 'Starting postgrey' 'n' rm -f /var/run/postgrey/postgrey.pid supervisorctl start postgrey } function _start_daemons_amavis() { _notify 'task' 'Starting amavis' 'n' supervisorctl start amavis } ########################################################################## # << Start Daemons ########################################################################## ########################################################################## # Start check for update postfix-accounts and postfix-virtual ########################################################################## function _start_changedetector() { _notify 'task' 'Starting changedetector' 'n' supervisorctl start changedetector } # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! # ! CARE --> DON'T CHANGE, unless you exactly know what you are doing # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! # shellcheck source=/dev/null . /usr/local/bin/helper_functions.sh if [[ ${DEFAULT_VARS[\"DMS_DEBUG\"]} -eq 1 ]] then _notify 'taskgrp' \"\" _notify 'taskgrp' \"#\" _notify 'taskgrp' \"#\" _notify 'taskgrp' \"# ENV\" _notify 'taskgrp' \"#\" _notify 'taskgrp' \"#\" _notify 'taskgrp' \"\" printenv fi _notify 'taskgrp' \"\" _notify 'taskgrp' \"#\" _notify 'taskgrp' \"#\" _notify 'taskgrp' \"# docker-mailserver\" _notify 'taskgrp' \"#\" _notify 'taskgrp' \"#\" _notify 'taskgrp' \"\" register_functions check setup fix misc start_daemons _notify 'taskgrp' \"\" _notify 'taskgrp' \"#\" _notify 'taskgrp' \"# $HOSTNAME is up and running\" _notify 'taskgrp' \"#\" _notify 'taskgrp' \"\" touch /var/log/mail/mail.log tail -fn 0 /var/log/mail/mail.log # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! # ! CARE --> DON'T CHANGE, unless you exactly know what you are doing # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! exit 0 "

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for SED, please visit: https://www.gnu.org/software/sed/manual/html_node/The-_0022s_0022-Command.html