set(1posix) -euxo%20pipefail
set or unset options and positional parameters
-e     When this option is on, if a simple command fails for any of the reasons listed in Consequences of
       Shell  Errors or returns an exit status value >0, and is not part of the compound list following a
       while, until, or if keyword, and is not a part of an AND  or  OR  list,  and  is  not  a  pipeline
       preceded by the ! reserved word, then the shell shall immediately exit.
-u     The shell shall write a message to standard error when it tries to expand a variable that  is  not
       set and immediately exit. An interactive shell shall not exit.
-x     The  shell shall write to standard error a trace for each command after it expands the command and
       before it executes it. It is unspecified whether the command that turns tracing off is traced.
-o     Write the current settings of the options to standard output in an unspecified format.

+o     Write the current option settings to standard output in a format that is suitable for  reinput  to
       the shell as commands that achieve the same options settings.
-f     The shell shall disable pathname expansion.
-a     When this option is on, the export attribute shall be set for each variable to which an assignment
       is  performed;  see  the  Base  Definitions volume of IEEE Std 1003.1-2001, Section 4.21, Variable
       Assignment. If the assignment precedes a utility name in a command, the export attribute shall not
       persist  in the current execution environment after the utility completes, with the exception that
       preceding one of the special built-in utilities causes the export attribute to persist  after  the
       built-in  has  completed.  If the assignment does not precede a utility name in the command, or if
       the assignment is a result of the operation of the getopts or read utilities, the export attribute
       shall persist until the variable is unset.
source manpages: set