Compresses a mail file.

    Format

      MAIL$MAILFILE_COMPRESS  context ,in_item_list ,out_item_list

1  –  Returns

    OpenVMS usage:cond_value
    type:         longword (unsigned)
    access:       write only
    mechanism:    by value

    Longword condition value. All utility routines return a condition
    value in R0. Condition values that can be returned by this
    routine are listed under Condition Values Returned.

2  –  Arguments

 context

    OpenVMS usage:context
    type:         longword (unsigned)
    access:       modify
    mechanism:    by reference
    Mail file context information to be passed to various mail file
    routines. The context argument is the address of a longword that
    contains mail file context information returned by MAIL$MAILFILE_
    BEGIN.

 in_item_list

    OpenVMS usage:itmlst_3
    type:         longword (unsigned)
    access:       read only
    mechanism:    by reference
    Item list specifying options for the routine. The in_item_list
    argument is the address of a list of item descriptors, each of
    which specifies an option and provides the information needed to
    perform the operation.

    The item list is terminated by longword value of 0.

3  –  Input Item Codes

 MAIL$_MAILFILE_DEFAULT_NAME

    MAIL$_MAILFILE_DEFAULT_NAME specifies the default file
    specification the Mail utility should use when opening a mail
    file. The buffer address field points to a character string 0 to
    255 characters long that defines the default file specification.

    Specify a value from 0 to 255 in the buffer length field of the
    item descriptor.

    If you specify the value 0 in buffer length field of the item
    descriptor, MAIL$MAILFILE_COMPRESS uses the current default
    directory as the default mail file specification.

    If you do not specify MAIL$_MAILFILE_DEFAULT_NAME, MAIL$MAILFILE_
    COMPRESS creates the default mail file specification from the
    following sources:

    o  Disk and directory defined in the caller's user authorization
       file (UAF)

    o  Subdirectory defined in the Mail user profile

    o  Default file type of .MAI

 MAIL$_MAILFILE_FULL_CLOSE

    The Boolean item code MAIL$_MAILFILE_FULL_CLOSE requests that
    the wastebasket folder be purged and that convert and reclaim
    operations be performed, if necessary.

    Specify the value 0 in the buffer length and buffer address
    fields of the item descriptor.

 MAIL$_MAILFILE_NAME

    MAIL$_MAILFILE_NAME specifies the name of a mail file to be
    opened. The buffer that the buffer address field points to
    contains a character string of 0 to 255 characters.

    Specify a value from 0 to 255 in the buffer length field of the
    item descriptor.

    If you do not specify MAIL$_MAILFILE_NAME, the default mail file
    name is MAIL.

 out_item_list

    OpenVMS usage:itmlst_3
    type:         longword
    access:       write only
    mechanism:    by reference
    Item list specifying the information you want the routine to
    return. The out_item_list argument is the address of a list of
    item descriptors, each of which describes an item of information.
    The list of item descriptors is terminated by longword value of
    0.

4  –  Output Item Code

 MAIL$_MAILFILE_RESULTSPEC

    When you specify MAIL$_MAILFILE_RESULTSPEC, the Mail utility
    returns the resultant mail file specification. The buffer address
    field of the item descriptor points to a buffer that receives a
    character string 0 to 255 characters long.

    Specify a value from 0 to 255 in the buffer length field of the
    item descriptor.

5  –  Description

    If you do not specify an input file, the MAIL$MAILFILE_
    COMPRESS routine compresses the currently open Mail file. The
    MAIL$MAILFILE_COMPRESS routine signals informational messages
    concerning the phase of the compression.

6  –  Condition Values Returned

    SS$_NORMAL         Normal successful completion.
    MAIL$_INVITMCOD    The specified item code is invalid.
    MAIL$_INVITMLEN    The specified item length is invalid.
    MAIL$_MISREQITEM   The required item is missing.
    MAIL$_NOTISAM      The message file is not an indexed file.
    RMS$_FNF           The specified file cannot be found.
    RMS$_SHR           The specified file is not shareable.
    SS$_ACCVIO         Access violation.
    SS$_IVDEVNAM       The specified device name is invalid.
    Any condition value returned by LIB$FIND_IMAGE_SYMBOL,
    LIB$RENAME_FILE, $CREATE, $OPEN, $PARSE, and $SEARCH.