INT 21,11 - Search for First Entry Using FCB

AH = 11h

DS:DX = pointer to unopened ~FCB~

on return:

AL = 00 if matching file found

= FF if file not found

- searches for first occurrence of filename specified in FCB

- FCB must have drive id, filename, and extension before call

- extended FCB can be used to specify a search criteria based

on attributes; hidden, system, label, and directory attributes

can be used to narrow the search (see ~FILE ATTRIBUTES~)

- after successful call DTA holds an unopened ~FCB~/~XFCB~ for

the requested file. Using any of the other FCB functions

destroys this ~DTA~ copy of the FCB/XFCB

- searching can be continued with the FCB find-next function

- "?" wildcard supported after DOS 2.1, "*" supported in DOS 3.x

- DOS 2.x can't find . and .. entries, DOS 3.x can (unless in root)

- see ~INT 21,12~