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How to change the default behavior of Bash?
Change the behavior of Bash where the default operation differs from the POSIX standard to match the standard (see Bash POSIX Mode ). This is intended to make Bash behave as a strict superset of that standard. Same as -p . Same as -v . Use a vi -style line editing interface. This also affects the editing interface used for read -e . Same as -x .
Where do hash command arguments go in Bash?
Locate and remember (hash) commands as they are looked up for execution. This option is enabled by default. All arguments in the form of assignment statements are placed in the environment for a command, not just those that precede the command name. Job control is enabled (see Job Control ). All processes run in a separate process group.
How does the set function work in Bash?
If no options or arguments are supplied, set displays the names and values of all shell variables and functions, sorted according to the current locale, in a format that may be reused as input for setting or resetting the currently-set variables. Read-only variables cannot be reset.
How are debug and return traps inherited in Bash?
If set, any trap on DEBUG and RETURN are inherited by shell functions, command substitutions, and commands executed in a subshell environment. The DEBUG and RETURN traps are normally not inherited in such cases. If no arguments follow this option, then the positional parameters are unset.
When to use the logical chain of directories in Bash?
By default, Bash follows the logical chain of directories when performing commands which change the current directory. For example, if /usr/sys is a symbolic link to /usr/local/sys then:
Why are Bash functions not processed in this mode?
In this mode, the $BASH_ENV and $ENV files are not processed, shell functions are not inherited from the environment, and the SHELLOPTS, BASHOPTS, CDPATH and GLOBIGNORE variables, if they appear in the environment, are ignored.
What should be included in the Bash manual?
The Bash manual page should be used as the definitive reference on shell behavior. An introduction to the shell. Some definitions used in the rest of this manual. The shell “building blocks”. Commands that are a part of the shell. Variables used or set by Bash. Features found only in Bash.
What kind of standard is Bash based on?
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. A space or tab character. A command that is implemented internally by the shell itself, rather than by an executable program somewhere in the file system.
When to use the same as B option in Bash?
All processes run in a separate process group. When a background job completes, the shell prints a line containing its exit status. Read commands but do not execute them. This may be used to check a script for syntax errors. This option is ignored by interactive shells. Set the option corresponding to option-name : Same as -a . Same as -B .