VMS Help ATTACH  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    Transfers control from your current process (which then
    hibernates) to the specified process.

    The ATTACH and SPAWN commands cannot be used if your terminal has
    an associated mailbox.

    Format

      ATTACH  [process-name]

1 - Parameter

 process-name

    Specifies the name of a parent process or spawned subprocess to
    which control passes. The process must already exist, be part of
    your current job, and share the same input stream as your current
    process. However, the process cannot be your current process or a
    subprocess created with the /NOWAIT qualifier.

    Process names can contain from 1 to 15 alphanumeric characters.
    If a connection to the specified process cannot be made, an error
    message is displayed.

    The process-name parameter is incompatible with the
    /IDENTIFICATION qualifier.

2 - Qualifier

 2.1 - /IDENTIFICATION

       /IDENTIFICATION=pid

    Specifies the process identification (PID) of the process to
    which terminal control will be transferred. Leading zeros can be
    omitted. The /IDENTIFICATION qualifier is incompatible with the
    process-name parameter.

    If you omit the /IDENTIFICATION qualifier, you must specify a
    process name.

3 - Examples

    1.$ ATTACH JONES_2

      The ATTACH command transfers the terminal's control to the
      subprocess JONES_2.

    2.$ ATTACH/IDENTIFICATION=30019

      The ATTACH command switches control from the current process
      to a process having the PID 30019. Notice that because the
      /IDENTIFICATION qualifier is specified, the process-name
      parameter is omitted.