Re: bash manual/info lacks examples

[Mirek Kwasniak <mirek@zind.ikem.pwr.wroc.pl>]

On Thu, Aug 05, 1999 at 08:49:31AM +0200, Andreas Tille wrote:
> Hello,
> 
> every time I read the bash manual to get help I'm missing
> examples for the basic usage of a builtin.  For instance
> I managed to write a simple shell script with a loop which
> increased a variable
> 
> i = 0;
> while [ $i -lt $MAX ] ; do
>   echo $i
>   let ...
> done
> 
> But I havn't my small loop script handy this time and wanted
> to know the syntax of let using `man bash` or `info bash`.
> I'm I stupid or what is the reason that I can't find out, how
> this expression after let has to be formed?


1) For builtins bash has also help:
 
   $ help let | less

2) Usage of man (my pager is `less')

   $ man bash
   /\<let\>
   n
   n

and I see

       let arg [arg ...]
              Each  arg  is an arithmetic expression to be evalu­
              ated (see ARITHMETIC EVALUATION).  If the last  arg
              evaluates to 0, let returns 1; 0 is returned other­
              wise.

I go to top of manpage and issue new search:

  <
  /ARITHMETIC EVALUATION

and see detailed description.

3) Usage of info

  $ info bash
  ^s let 
    ^   ^
    ^---^------------------ here arre spaces
  ^s

and I see

`let'
          let EXPRESSION [EXPRESSION]
     The `let' builtin allows arithmetic to be performed on shell
     variables.  Each EXPRESSION is evaluated according to the rules
     given below in *Note Shell Arithmetic::.  If the last EXPRESSION
     evaluates to 0, `let' returns 1; otherwise 0 is returned.
 
after that I go to topic "Shell Arithmetic".

Regards

Mirek