/sys$common/syshlp/helplib.hlb RMS, NAM  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    The name (NAM) block provides additional fields for extended file
    specification use, including parsing and obtaining the actual
    file specification used for a file operation. On Alpha systems,
    the long name block (NAML) can optionally take the place of a NAM
    block (see NAML).

    The following table lists the symbolic offset, the size in bytes,
    and a brief description of each field.

    Offset             Size               Description

    NAM$B_BID          1                  Block identifier
    NAM$B_BLN          1                  Block length
    NAM$B_DEV          1                  Device string length
    NAM$L_DEV          4                  Device string address
    NAM$W_DID          6                  Directory identification
    NAM$B_DIR          1                  Directory string length
    NAM$L_DIR          4                  Directory string address
    NAM$T_DVI          16                 Device identification
    NAM$L_ESA          4                  Expanded string area
                                          address
    NAM$B_ESL          1                  Expanded string length
    NAM$B_ESS          1                  Expanded string area size
    NAM$W_FID          6                  File identification
    NAM$W_FIRST_WILD_  2                  The topmost directory level
    DIR                                   to contain a wildcard.
    NAM$L_FNB          4                  File name status bits
    NAM$W_LONG_DIR_    2                  Total number directories
    LEVELS
    NAM$B_NAME         1                  File name string length
    NAM$L_NAME         4                  File name string address
    NAM$B_NMC          1                  Name characteristics
    NAM$B_NODE         1                  Node name string length
    NAM$L_NODE         4                  Node name string address
    NAM$B_NOP          1                  Name block options
    NAM$L_RLF          4                  Related file NAM or NAML
                                          block address
    NAM$L_RSA          4                  Resultant string area
                                          address
    NAM$B_RSL          1                  Resultant string length
    NAM$B_RSS          1                  Resultant string area size
    NAM$B_TYPE         1                  File type string length
    NAM$L_TYPE         4                  File type string address
    NAM$B_VER          1                  File version string length
    NAM$L_VER          4                  File version string address
    NAM$L_WCC          4                  Wildcard context