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Full Discussion: Question on using "[[ ]]" in lieu of IF Construct
Top Forums Shell Programming and Scripting Question on using "[[ ]]" in lieu of IF Construct Post 302285730 by cfajohnson on Monday 9th of February 2009 02:33:27 PM
Old 02-09-2009
Quote:
Originally Posted by otheus
There is no standard way, however, of doing negation in the UNIX shell using the && || constructs. One can, however, do something like this:
Code:
not() { 
  "$@"
  if [ $? = 0 ]; then return 1; else return 0; fi
}

# not true || echo false
false
# not false && echo true
true


What's wrong with the negation operator?

Code:
if ! some_command
then
  echo command failed
fi

 

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LEARN ABOUT SUNOS

start-domain

asadmin-start-domain(1AS)					   User Commands					 asadmin-start-domain(1AS)

NAME

       asadmin-start-domain, start-domain - starts the given domain

SYNOPSIS

       start-domain [--domaindir install_dir/domains] [--terse=false] [--echo=false] [--verbose=false] [--debug] [domain_name]

       start-domain  starts the specified domain. If there is only one domain in the default domain directory (install_dir/domains), then no oper-
       and is required to start the domain. However, if there is more than one domain, the domain operand must be specified. This command can only
       be run locally.

OPTIONS

       --domaindir	       directory where the domain is to be started. If specified, path must be accessible in the filesystem. If not speci-
			       fied, the domain is started in the default install_dir/domains directory.

       --terse		       indicates that any output data must be very concise, typically avoiding human-friendly sentences and favoring well-
			       formatted data for consumption by a script. Default is false.

       --echo		       setting to true will echo the command line statement on the standard output. Default is false.

       --verbose	       by  default this flag is set to false. If set to true, detailed server startup output is displayed. Press CTRL-C to
			       kill the server. Press CTRL- to print a thread dump.

       --debug		       by default this flag is set to false. If set to true, the server is started in debug mode and prints the JPDA  port
			       on the console.

OPERANDS

       domain_name	       name of the domain. Must be a unique name.

       Example 1: Using start-domain

       asadmin> start-domain sampleDomain
       Starting Domain sampleDomain, please wait.
       Domain sampleDomain started

       Where: the sampleDomain domain is started.

EXIT STATUS

       0		       command executed successfully

       1		       error in executing the command

       asadmin-create-domain(1AS), asadmin-delete-domain(1AS), asadmin-stop-domain(1AS), asadmin-list-domains(1AS)

J2EE 1.4 SDK							    March 2004						 asadmin-start-domain(1AS)
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