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A kernel panic is an action taken by an operating system upon detecting an internal fatal error from which it cannot safely recover. The term is largely specific to Unix and Unix-like systems; for Microsoft Windows operating systems the equivalent term is "stop error" (or, colloquially, "Blue Screen of Death"). The kernel routines that handle panics, known as panic() in AT&T-derived and BSD Unix source code, are generally designed to output an error message to the console, dump an image of kernel memory to disk for post-mortem debugging and then either wait for the system to be manually rebooted, or initiate an automatic reboot.〔http://www.unix.com/man-page/FreeBSD/9/panic/〕 The information provided is of a highly technical nature and aims to assist a system administrator or software developer in diagnosing the problem. Kernel panics can also be caused by errors originating outside of kernel space. For example, many Unix OSes panic if the init process, which runs in userspace, terminates.〔(HP-UX init died panic )〕〔(IRIX init died panic )〕==History== The Unix kernel maintains internal consistency and runtime correctness with assertions as the fault detection mechanism. The basic assumption is that the hardware and the software should perform correctly and a failure of an assertion results in a ''panic'', i.e. a voluntary halt to all system activity. The kernel panic was introduced in an early version of Unix and demonstrated a major difference between the design philosophies of Unix and its predecessor Multics. Multics developer Tom van Vleck recalls a discussion of this change with Unix developer Dennis Ritchie: I remarked to Dennis that easily half the code I was writing in Multics was error recovery code. He said, "We left all that stuff out. If there's an error, we have this routine called panic, and when it is called, the machine crashes, and you holler down the hall, 'Hey, reboot it.'"〔(Unix and Multics )〕 The original panic() function was essentially unchanged from Fifth Edition UNIX to the VAX-based UNIX 32V and output only an error message with no other information, then dropped the system into an endless idle loop.Source code of panic() function in UNIX V6:〔(Source code /usr/sys/ken/prf.c from UNIX V6 )〕/ * * In case console is off, * panicstr contains argument to last * call to panic. */ char *panicstr; / * * Panic is called on unresolvable * fatal errors. * It syncs, prints "panic: mesg" and * then loops. */ panic(s) char *s; As the Unix codebase was enhanced, the panic() function was also enhanced to dump various forms of debugging information to the console.抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Kernel panic」の詳細全文を読む スポンサード リンク
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