Q58800: Using _dos_findfirst() Function to Retrieve Disk Volume

Article: Q58800
Product(s): See article
Version(s): 5.10
Operating System(s): MS-DOS
Keyword(s): ENDUSER | s_quickc 2.00 s_quickasm 2.01 | mspl13_c
Last Modified: 26-FEB-1990

Question:

I am using the _dos_findfirst() function to find my disk volume. I use
the _A_VOLID attribute to get the disk volume and it works correctly,
except when I get a volume name greater than eight characters. Then, I
get a period embedded in the middle of my string. For example, if my
volume name is "VOLUMENAME", _dos_findfirst returns "VOLUMENA.ME". Why
does the period get embedded in the string?

Response:

Volume labels are a specific type of directory entry specified by
setting bit 3 in the attribute field to 1 or 0x08. They are a special
type of file that can only be in the root directory. The maximum
number of characters a volume label can have is 11 characters (8
characters for the filename followed by a three-character extension).

The C run-time function _dos_findfirst() will return the volume label
in a file format since DOS stores the volume label in the file format.

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