Abstract: In one aspect, the present disclosure describes a process for maintaining file allocation tables (FATs) for a volume of storage medium. The process includes triggering, by a write operation, modification of data in an existing sector of a data file by writing of data to a new sector of the storage medium. The process also includes writing revised used/unused sector information into one FAT and setting a variable indicative of a number of FATs (NOF) to a first value. The process additionally includes copying the one FAT to another FAT and re-setting the variable to a second value.

Abstract: A method and system for automatically running a program stored on a medium upon detection of insertion of the medium into a drive are provided. The operating system periodically polls the drive regarding the status of the drive. After receiving a response from the drive regarding the drive's status, the operating system determines whether the drive's status has changed. If the drive's status has changed, the operating system broadcasts a message indicating the change in the drive's status. When the shell receives a message from the operating system indicating a change in the drive's status, the shell determines whether the change in the drive's status indicates that a medium has been inserted into the drive. If the change in the drive's status indicates that a medium has been inserted into the drive, the shell searches for a predefined file on the medium. The shell then runs a program stored on the medium that is specified in the predefined file.

Abstract: After it is determined that a memory storage device supports media status notification (MSN), the operating system (OS) enables MSN by sending a command to the device that disables the ejection mechanism within the device. The operating system commences MSN operation using one of two alternative modes. In an Asynch mode, the OS issues a single status command to the device. The single status command is stored in a queue pending the occurrence of a media event related to the device's removable medium, such as an ejection request. After the media event occurs, the device completes the status command by altering the removable medium's status and reporting the altered status within a data packet sent to the OS. In a Polling mode, the OS periodically sends status commands to the device. The device ignores the status commands until a media event related to the device's removable medium occurs.

Abstract: A system and method are disclosed for executing, in a multitasking operating system, an application program that accesses a protected resource directly without mediation by the operating system. For example, the application can be a backup application and the resource can be a floppy disk drive, QIC tape drive, or other storage device. The method of the invention can be executed in a computer system having a processor, a storage device, and a device control mechanism for controlling operations of the storage device responsively to commands issued by the processor. The device control mechanism can be, for example, a floppy disk controller chip if the storage device is, for example, a floppy disk drive. According to the invention, the processor executes the application program as a task of the operating system. The operating system includes a software component, such as a device driver, for issuing commands to the device control mechanism.

Abstract: A system and method are disclosed for executing, in a multitasking operating system, an application program that accesses a protected resource directly without mediation by the operating system. For example, the application can be a backup application and the resource can be a floppy disk drive, QIC tape drive, or other storage device. The method of the invention can be executed in a computer system having a processor, a storage device, and a device control mechanism for controlling operations of the storage device responsively to commands issued by the processor. The device control mechanism can be, for example, a floppy disk controller chip if the storage device is, for example, a floppy disk drive. According to the invention, the processor executes the application program as a task of the operating system. The operating system includes a software component, such as a device driver, for issuing commands to the device control mechanism.

Abstract: A method and system for caching data that improve the efficiency of a cache are provided. Generally, three types of data are stored in a cache constructed according to the principles of the present invention. These types of data include: (1) path tables, (2) directories, and (3) files. Path tables include data regarding all of the directories on a storage medium, directories include data regarding all of the subdirectories and files in each directory, and files include the actual file data. The preferred embodiment of the cache logically includes eight regions. These regions include (in order of preferred descending priority): (1) path table, (2) directory, (3) two-access, (4) zero-access or prefetch, (5) sequential-locked, (6) one-access, (7) discarded, and (8) invalid.

Abstract: A method and system for determining insertions and removals of floppy disks in a floppy disk drive. By monitoring states of a write protect signal, the present invention determines when floppy disks of a predetermined type are inserted into, and removed from, a floppy disk drive. More specifically, the present invention evaluates current states of the write protect signal in light of a default state of the write protect signal to determine when these floppy disks are inserted into, and removed from, the floppy disk drive.

Abstract: A method and system for caching data that improve the efficiency of a cache are provided. Generally, three types of data are stored in a cache constructed according to the principles of the present invention. These types of data include: (1) path tables, (2) directories, and (3) files. Path tables include data regarding all of the directories on a storage medium, directories include data regarding all of the subdirectories and files in each directory, and files include the actual file data. The preferred embodiment of the cache logically includes eight regions. These regions include (in order of preferred descending priority): (1) path table, (2) directory, (3) two-access, (4) zero-access or prefetch, (5) sequential-locked, (6) one-access, (7) discarded, and (8) invalid.