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− | These definitions are used throughout the remainder of this manual.
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− | POSIX
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− | : A family of open system standards based on Unix. Bash is primarily concerned with the Shell and Utilities portion of the POSIX 1003.1 standard. | + | |
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− | blank
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− | : A space or tab character.
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− | builtin
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− | : A command that is implemented internally by the shell itself, rather than by an executable program somewhere in the file system.
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− | control operator
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− | : A token that performs a control function. It is a newline or one of the following: ‘||’, ‘&&’, ‘&’, ‘;’, ‘;;’, ‘|’, ‘|&’, ‘(’, or ‘)’.
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− | exit status
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− | : A unit of text that is the result of one of the shell expansions. After expansion, when executing a command, the resulting fields are used as the command name and arguments.
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− | field
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− | : A unit of text that is the result of one of the shell expansions. After expansion, when executing a command, the resulting fields are used as the command name and arguments.
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− | | + | |
− | filename
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− | : A string of characters used to identify a file.
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− | job
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− | : A set of processes comprising a pipeline, and any processes descended from it, that are all in the same process group.
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− | job control
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− | : A mechanism by which users can selectively stop (suspend) and restart (resume) execution of processes.
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− | metacharacter
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− | : A character that, when unquoted, separates words. A metacharacter is a blank or one of the following characters: ‘|’, ‘&’, ‘;’, ‘(’, ‘)’, ‘<’, or ‘>’.
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− | name
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− | : A word consisting solely of letters, numbers, and underscores, and beginning with a letter or underscore. Names are used as shell variable and function names. Also referred to as an identifier.
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− | operator
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− | : A control operator or a redirection operator. See [[#Redirections|Redirections]], for a list of redirection operators. Operators contain at least one unquoted metacharacter.
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− | process group
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− | : A collection of related processes each having the same process group ID.
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− | process group ID
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− | : A unique identifier that represents a process group during its lifetime.
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− | reserved word
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− | : A word that has a special meaning to the shell. Most reserved words introduce shell flow control constructs, such as for and while.
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− | return status
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− | : A synonym for exit status.
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