* NSH Added support for set [{+|-}{e|x|xe|ex}] [<name> <value>]
Set the 'exit on error control' and/or 'print a trace' of
commands when parsing scripts in NSH.
The settinngs are in effect from the point of exection,
until they are changed again, or in the case of the init
script, the settings are returned to the default settings
when it exits.
Included child scripts will run with the parents settings
and changes made in the child script will effect the parent
on return.
Use 'set -e' to enable and 'set +e' to disable (ignore) the exit
condition on commands. The default is -e. Errors cause script to
exit.
Use 'set -x' to enable and 'set +x' to disable (silence) printing
a trace of the script commands as they are ececuted. The default
is +x. No printing of a trace of script commands as they are
executed.
Print expanded variables if -x
* Added comments only on how to use the set +e and and set -x
* Spelling NSH_PFALG_* -> NSH_PFLAG_*
David Sidrane