Using grep with test and without using [[ ]] Post: 303029212

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Top Forums Shell Programming and Scripting Using grep with test and without using [[ ]] Post 303029212 by wisecracker on Wednesday 23rd of January 2019 07:26:44 AM

01-23-2019

Registered User

Hi MadeInGermany...
(Or anyone...)

Relative to this thread as you have used 'case....esac':
What is the reasoning behind ;;, why 2 semicolons instead of 1, after each command inside a 'case' statement?
I have always wondered as I can't find any mention of it.
A question to help our newbie friend to understand too.

Code:

Last login: Wed Jan 23 12:04:15 on ttys000
AMIGA:amiga~> help case
case: case WORD in [PATTERN [| PATTERN]...) COMMANDS ;;]... esac
    Selectively execute COMMANDS based upon WORD matching PATTERN.  The
    `|' is used to separate multiple patterns.
AMIGA:amiga~> _

And from the manual, (man bash):

Code:

       case word in [ [(] pattern [ | pattern ] ... ) list ;; ] ... esac
              A case command first expands word, and tries to match it against
              each pattern in turn, using the same matching rules as for path-
              name expansion (see Pathname  Expansion  below).   The  word  is
              expanded  using  tilde  expansion, parameter and variable expan-
              sion, arithmetic  substitution,  command  substitution,  process
              substitution  and  quote  removal.   Each  pattern  examined  is
              expanded using tilde expansion, parameter  and  variable  expan-
              sion, arithmetic substitution, command substitution, and process
              substitution.  If the shell option nocasematch is  enabled,  the
              match  is  performed  without  regard  to the case of alphabetic
              characters.  When a match is found, the  corresponding  list  is
              executed.   After  the  first  match,  no subsequent matches are
              attempted.  The exit status is zero if no pattern matches.  Oth-
              erwise,  it  is  the exit status of the last command executed in
              list.

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LEARN ABOUT X11R4

fc-pattern

FC-PATTERN(1)                                                                                                                        FC-PATTERN(1)

NAME

       fc-pattern - parse and show pattern

SYNOPSIS

       fc-pattern [ -cdVh ] [ --config ] [ --default ] [ -f format | --format format ] [ --version ] [ --help ]
           [ pattern  [ element ... ]  ]

DESCRIPTION

       fc-pattern  parses  pattern (empty pattern by default) and shows the parsed result.  If --config is given, config substitution is performed
       on the pattern before being displayed.  If --default is given, default substitution is performed on the pattern before being displayed.

       If any elements are specified, only those are printed.

OPTIONS

       This program follows the usual GNU command line syntax, with long options starting with two dashes (`-').  A summary of options is included
       below.

       -c --config
              Perform config substitution on pattern.

       -d --default
              Perform default substitution on pattern.

       -f --format format
              Format output according to the format specifier format.

       -V --version
              Show version of the program and exit.

       -h --help
              Show summary of options.

       pattern
              Parses and displays pattern (uses empty pattern by default).

       element
              If set, the element property is displayed for parsed pattern.

SEE ALSO

       FcNameParse(3)  FcConfigSubstitute(3)  FcDefaultSubstitute(3)  FcPatternPrint(3)  FcPatternFormat(3)  fc-cat(1)  fc-cache(1) fc-list(1) fc-
       match(1) fc-query(1) fc-scan(1)

       The fontconfig user's guide, in HTML format: /usr/share/doc/fontconfig/fontconfig-user.html.

AUTHOR

       This manual page was updated by Behdad Esfahbod <behdad@behdad.org>.

                                                                   16 April 2012                                                     FC-PATTERN(1)

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