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command separator

summary

    This subchapter looks at the command separator in UNIX or Linux.

    The semicolon ( ; ) is used as a command separator.

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command separator

    This subchapter looks at the command separator in UNIX or Linux.

semicolon

    The semicolon ( ; ) is used as a command separator.

    You can run more than one command on a single line by using the command separator, plaing the semicolon between each command.

    $ date; who am i
    Mon Aug 27 19:15:41 PDT 2012
    admin    ttys000  Aug 27 17:50
    $

    It does not matter if you have a space before the semicolon or not. Use whichever method is more readable and natural for you.

    $ date ; who am i
    Mon Aug 27 19:15:41 PDT 2012
    admin    ttys000  Aug 27 17:50
    $

    Each command is processed in order, as if you had typed each individually, with the exception that the line with the prompt is only displayed once, at the end of the series of commands.

    If you forget the semicolon, you will get an error message. The following two examples are from different systems.

    $ date who am i
    date: illegal time format
    $

    $ date who am i
    date: bad conversion
    $

    The semicolon is a common terminator or separator in many common programming languages, including Ada, C, Java, Pascal, Perl, PHP, and PL/I.

    Many programmers automatically place the semicolon at the end of any shell command. The shell is fine with this.

    $ date;
    Mon Aug 27 19:15:41 PDT 2012
    $

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