Int 21H, AH=37H, AL=00H

2 and higher

GET SWITCH CHARACTER

      AX = 3700h

AL = status

          00h successful
              DL = current switch character
          FFh unsupported subfunction

Determine the character which is used to introduce command switches. This setting is ignored by MS-DOS commands in version 4.0 and higher, but is honored by many third-party programs and by Novell DOS 7 external commands

BUG: Novell DOS 7's COMMAND.COM (prior to Update 15) fails to honor the SwitChar setting for internal commands even though COMMAND.COM honors it in its own command tail (i.e. COMMAND /?); even in Update 15, internal commands fail to honor SwitChar for the /? help option

documented in some OEM versions of some releases of DOS

supported by OS/2 compatibility box

always returns AL=00h/DL=2Fh for MS-DOS 5+ and DR DOS 3.41-6.0

Novell DOS 7 COMMAND.COM indicates switch characters other than '/' by changing the first backslash (and only the first one) in the path it prints for PROMPT $p with a forward slash

AX=3701h

Text based on Ralf Brown Interrupt List Release 61