Sorry but I've never done this before,I have some figures that need to have such poses to work correctly,eg a boot that need to have M4 feet hidden.How I can do that?Is it a complicated thing?Thanks a lot

It would look like this:
"
{

version
    {
    number 7.0
    }

actor rFoot:1
    {
              off
    }
actor lFoot:1
    {
              off
    }
}
"

If you copy everything between the quotes, paste it into a text editor and save it with the .pz2 extension it should work... change 'off' to 'on' to create a 'show' pose. Obviously can be adapted for any other body parts.

Good luck!

thanks, I just have to write these lines?

No need for a pose, for any body part just select it then in its properties deselect the box labelled "Visible"

Yes, start at the first " { " and end at the last " } ". Make sure you retain the indents, they seem to be important.

I'd recommend Notepad ++ for this kind of stuff.

It's that if the body parts are more than one it would be better to have a pose that hide those parts

but i have to edit the cr2 to create this file?

No. create a text file called ToesHide.pz2 that looks like this. Save to you pose folder-directory. You can put it in another folder in the the pose folder-directory like I have called HideBodyParts.
Case of the letters is important when specifying a body part rToe will work whereas Rtoe or rtoe will not.

{
version
    {
    number 4
    }
actor BODY
    {
    }
actor rToe
    {
    off
    }
actor lToe
    {
    off
    }
figure
    {
    }
}

In the free stuff I found  one that I have never used that you can download and look at and maybe use

http://www.renderosity.com/mod/freestuff/details.php?item_id=28616

thank you very much!

Just FYI.

Line indentation in Poser files is only to make it easier for humans to read. Poser does not actually require it.

However Poser Python scripts DO take account of the indentation. (As do all Python scripts).

Another FYI:

If you make a hide pose, it's best to make an un-hide pose as well.   Looks just like the example, only the key word is "on" instead of "off."

And lastly....

Although there is not even an ad-hoc standard, many creators attempt to adhere to some variation of the below;

MAT poses change materials
MOR poses adjust morphs
SET poses are multi-function-poses, to change joint params...or hide/unhide body parts.

(Oh by the way...if you didn't figure it out already, a pose file is nothing but a text file -- normally .txt -- that's had the suffix .pz2 applied instead.)

If it helps, feel free to use my hide/ show hands and hide/ show feet poses as a starting point.