signing an verifying data without the need of files

[Björn Mayer]

  Hi,

  I would like to sign text without first having to create a file where I  
have to write the text into.
  --> is it possible to hand the text directly from the standard input?

  As well I would like to obtain the signature without having to open the  
created ".asc" file.
  --> is it possible to redirect the file output to the standard output?

  Of course, the same questions do occure concerning verification!
  Currently, I'm writing a Java API for a project of mine and would like to  
speed up the performance
  by avoiding slow file operations...

  Best regards,
   Bjorn