- The UNIX System writes out a memory image of a terminated
- process when any of various errors occur. See _\bs_\bi_\bg_\bv_\be_\bc(2) for
- the list of reasons; the most common are memory violations,
- illegal instructions, bus errors, and user-generated quit
- signals. The memory image is called `core' and is written
- in the process's working directory (provided it can be; nor-
- mal access controls apply).
-
- The maximum size of a _\bc_\bo_\br_\be file is limited by _\bs_\be_\bt_\br_\bl_\bi_\bm_\bi_\bt(2).
- Files which would be larger than the limit are not created.
-
- The core file consists of the _\bu. area, whose size (in pages)
- is defined by the UPAGES manifest in the <_\bs_\by_\bs/_\bp_\ba_\br_\ba_\bm._\bh> file.
- The _\bu. area starts with a _\bu_\bs_\be_\br structure as given in
- <_\bs_\by_\bs/_\bu_\bs_\be_\br._\bh>. The remainder of the core file consists first
- of the data pages and then the stack pages of the process
- image. The amount of data space image in the core file is
- given (in pages) by the variable _\bu__\bd_\bs_\bi_\bz_\be in the _\bu. area.
- The amount of stack image in the core file is given (in
- pages) by the variable _\bu__\bs_\bs_\bi_\bz_\be in the _\bu. area. The size of
- a ``page'' is given by the constant NBPG (also from
- <_\bs_\by_\bs/_\bp_\ba_\br_\ba_\bm._\bh>).
-
- In general the debugger _\ba_\bd_\bb(1) is sufficient to deal with
- core images.
+ A small number of signals which cause abnormal termination of a process
+ also cause a record of the process's in-core state to be written to disk
+ for later examination by one of the aviailable debuggers. (See
+ sigaction(2).) This memory image is written to a file named c\bco\bor\bre\be in the
+ working directory; provided the terminated process had write permission
+ in the directory, and provided the abnormality did not caused a system
+ crash. (In this event, the decision to save the core file is arbitrary,
+ see savecore(8).)
+
+ The maximum size of a c\bco\bor\bre\be file is limited by setrlimit(2). Files which
+ would be larger than the limit are not created.
+
+ The c\bco\bor\bre\be file consists of the _\bu. area, whose size (in pages) is defined
+ by the UPAGES manifest in the <_\bs_\by_\bs_\b/_\bp_\ba_\br_\ba_\bm_\b._\bh> file. The _\bu. area starts
+ with a _\bu_\bs_\be_\br structure as given in <_\bs_\by_\bs_\b/_\bu_\bs_\be_\br_\b._\bh>. The remainder of the c\bco\bor\bre\be
+ file consists of the data pages followed by the stack pages of the pro-
+ cess image. The amount of data space image in the c\bco\bor\bre\be file is given (in
+ pages) by the variable _\bu_\b__\bd_\bs_\bi_\bz_\be in the _\bu. area. The amount of stack image
+ in the core file is given (in pages) by the variable _\bu_\b__\bs_\bs_\bi_\bz_\be in the _\bu.
+ area. The size of a ``page'' is given by the constant NBPG (also from
+ <_\bs_\by_\bs_\b/_\bp_\ba_\br_\ba_\bm_\b._\bh>).
projects / unix-history / blobdiff