JP2560631B

PURPOSE:To easily prevent the outsiders from having accesses to the window that can be operated by only the person in question by performing the collation of passwords and clearing the corresponding protection flag set on a window management table to cancel a protection mode. CONSTITUTION:A protection means 8 identifies the number of a window and also sets a protection flag on a window management table 5. Thus a keyboard command control means 4 outputs the input data as a user password as long as the protection flag read out of the table 5 requests the protection. Then a password check means 9 disuses the input data when the password received from the means 4 is not identical with a set password. Meanwhile the means 9 cancels the protection of the corresponding window number of the table 5 when the coincidence is confirmed between the preceding two passwords. A keyboard command processing means 7 sends the window number to the means 8 when the data given from the means 4 shows a protection command.