kernel crash/panic/core dump

[Anonymous]

Hello there,

Does anyone know why it happens?

A C/C++ program is written to query the status of external printer. THe program does the followings:
1. open the node /dev/usb/lp0
2. Send an ioctl command with control code (magic number) 0x84005001 to get the device ID string.
When the program ran on 2.4.18 kernel, Kernel on few occasions resulted in crash, panic, and/or core dump, when the device was disconnected while the kernel was in the process of sending the ioctl command. On several occasions it returning EBADF errno (indicating bad file descriptor). However, the Perl script executing a similar algorithm results in a consistent behavior; meaning does not lead to system crash or core dump.

Thanks,