The resident and non-resident name tables define the ASCII names and ordinal numbers for exported entries in the module. In addition the first entry in the resident name table contains the module name. These tables are used to translate a procedure name string into an ordinal number by searching for a matching name string. The ordinal number is used to locate the entry point information in the entry table. The resident name table is kept resident in system memory while the module is loaded. It is intended to contain the exported entry point names that are frequently dynamicaly linked to by name. Non-resident names are not kept in memory and are read from the EXE file when a dynamic link reference is made. Exported entry point names that are infrequently dynamicaly linked to by name or are commonly referenced by ordinal number should be placed in the non-resident name table. The trade off made for references by name is performance vs memory usage. Import references by name require these tables to be searched to obtain the entry point ordinal number. Import references by ordinal number provide the fastest lookup since the search of these tables is not required.

Installable File Systems, Physical Device Drivers, and Virtual Device Drivers are closed after the file is loaded. Any refeference to the non-resident name table after this time will fail. The strings are CASE SENSITIVE and are NOT NULL TERMINATED. Each name table entry has the following format 

          旼컴컴쩡컴컴컴컴컴컴컴컴�     컴컴컴쩡컴컴컴컴컴�
      00h � LEN �    ASCII STRING  . . .      � ORDINAL # �
          읕컴컴좔컴컴컴컴컴컴컴컴�     컴컴컴좔컴컴컴컴컴�

Resident or Non-resident Name Table Entry

LEN = DB String Length. This defines the length of the string in bytes. A zero length indicates there are no more entries in table. The length of each ascii name string is limited to 127 characters. The high bit in the LEN field (bit 7) is defined as an Overload bit. This bit signifies that additional information is contained in the linear EXE module and will be used in the future for parameter type checking.

ASCII STRING = DB ASCII String. This is a variable length string with it's length defined in bytes by the LEN field. The string is case case sensitive and is not null terminated.

ORDINAL # = DW Ordinal number. The ordinal number in an ordered index into the entry table for this entry point.

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