The type of message box that you want to display is determined by the characters in the string following the "/m" or "/M" switch, without intervening spaces. If no characters are added after the letter "m" or "M", a simple OK box is displayed with just an OK button that you can click to close the box, returning control to the calling program, or press ENTER or ESC.

The meaning of the characters in the definition string is shown below. Options are case-sensitive. For more information, refer to the Windows SDK reference.

a: Abort-retry-ignore
c: Cancel-try-continue
r: Retry-cancel
o: OK (same as default)
O: OK-Cancel
y: Yes-no
Y: Yes-no-cancel
!: Include exclamation icon
w: Include warning icon
i, *: Include information icon
q, h: Include query icon
s: Include stop icon
e: Include error icon
1: First button is default (assumed)
2: Second button is default
3: Third button is default
4: Fourth button is default (for future use)
A: Dialogue is application modal
S: Dialogue is system modal
t: Dialogue is task modal
D: Default desktop only
R: Text right justified
L: right-to-left reading (Hebrew, etc.)
F: Foreground
T: Topmost

The character determining the buttons in the dialogue must be the first in the definition string. The rest of the options may occur in any order.

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Defining the Message Box