Q36397: Must Use A$=INKEY$ after SLEEP to Clear Keyboard Buffer
Article: Q36397 Product(s): See article Version(s): 4.00 4.00b 4.50 Operating System(s): MS-DOS Keyword(s): ENDUSER | B_BasicCom | mspl13_basic Last Modified: 15-DEC-1989 The SLEEP statement was introduced in QuickBASIC Version 4.00b and in Microsoft BASIC Compiler Version 6.00 for MS-DOS and MS OS/2. SLEEP does not clear the buffer when a key is pressed. Therefore, the next input statement will read the pressed keys to clear prior SLEEP commands. This information applies to Microsoft QuickBASIC Versions 4.00b and 4.50 for MS-DOS, to Microsoft BASIC Compiler Versions 6.00 and 6.00b for MS-DOS and MS OS/2, and to Microsoft BASIC PDS Version 7.00 for MS-DOS and MS OS/2. The following code example demonstrates the problem with a workaround: CLS FOR i = 1 TO 5 PRINT "press a key please" SLEEP ' If you want to clear the buffer, insert the following statement: ' x$ = INKEY$ NEXT CLS ' If you do not clear the buffer, this INPUT prompts with a print ' of the 5 characters pressed in the FOR loop above, and the value of ' a$ will be those 5 characters plus any entered at the prompt. INPUT a$ PRINT a$
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