Dear Adarsh Babu Kalepalli, In message <cajgxa7daf5+gu1f2jmkrys2yekg-xw6hzyokdknh2kttydo...@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, see [1]: 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. Best regards, Wolfgang Denk -- 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: w...@denx.de "I like your game but we have to change the rules."