[cmd] Notation for "mandatory" and "optional" parameters in "help shell_cmd" output
wd at denx.de
Sun Mar 1 17:39:13 CET 2020
Dear Adarsh Babu Kalepalli,
In message <CAJgxa7dAF5+gu1F2JMKrYs2YEKg-Xw6hzyOKDKNH2ktTyDoFCw at mail.gmail.com> you wrote:
> When we type "help shell_command" at u-boot console.
> The syntax for the command usage is displayed.
> In most of the cases I noticed parameters enclosed in '' or/and '<>'
> or just the sub-command string is provided.
> From the help of most of the commands, and on using them I observed that
> parameters enclosed in
> -'' could be optional
> -'<>' could be mandatory
> In some cases, the mandatory parameters were not enclosed in "<>" .
> For ex.
> env ask name [message] [size] - ask for environment variable
> env edit name - edit environment variable
> env exists name - tests for existence of variable
> in the above case "name" seems to be a mandatory parameter.
> Could you please let me know the notation we follow to indicate the
> mandatory and optional input parameters for shell commands in their syntax
> (displayed through help) ??
In general we try to follow the SYNOPSIS style of UNIX™ man pages,
For commands, this shows the syntax of the command and its
arguments (including options); boldface is used for as-is
text and italics are used to indicate replaceable arguments.
Brackets () surround optional arguments, vertical bars (|)
separate choices, and ellipses (...) can be repeated.
Only we don't have bold or italic fonts, so bold is often omitted
and in some cases we may write <italics>.
But note that these texts have been written buy a large number of
developers, so don't expect strict consistency. But as usual:
patches for cleanup are always welcome.
DENX Software Engineering GmbH, Managing Director: Wolfgang Denk
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
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