How to produce a core

How to produce a core

[gshan]

This morning, I tried command "kill -7 [pid]" but didn't see the core 
file. Anybody has ideas?

bash-2.05b# ps
PID   USER     COMMAND
    1 0        init  
    2 0        [ksoftirqd/0]
    3 0        [watchdog/0]
    4 0        [events/0]
    5 0        [khelper]
    6 0        [kthread]
   36 0        [kblockd/0]
   38 0        [kseriod]
   50 0        [pdflush]
   51 0        [pdflush]
   52 0        [kswapd0]
   53 0        [aio/0]
  171 0        -sh 
  174 0        [rpciod/0]
  182 0        bash 
  198 0        gdi_trans 16777471 0 0 12 1 0 10000 8000 0 0 0 1 1 
  204 0        ps 
bash-2.05b# kill -7 198
bash-2.05b# ps
PID   USER     COMMAND
    1 0        init  
    2 0        [ksoftirqd/0]
    3 0        [watchdog/0]
    4 0        [events/0]
    5 0        [khelper]
    6 0        [kthread]
   36 0        [kblockd/0]
   38 0        [kseriod]
   50 0        [pdflush]
   51 0        [pdflush]
   52 0        [kswapd0]
   53 0        [aio/0]
  171 0        -sh 
  174 0        [rpciod/0]
  182 0        bash 
  205 0        ps 
[1]+  Bus error               gdi_trans 16777471 0 0 12 1 0 10000 8000 0 0 0 1 1

Re: How to produce a core

[Willy Tarreau]

On Thu, May 24, 2007 at 11:28:15AM +0800, gshan wrote:
> This morning, I tried command "kill -7 [pid]" but didn't see the core 
> file. Anybody has ideas?

do the following before starting your program :

# ulimit -c unlimited

You can check before and after that the core size changed from 0 to
"unlimited" :

# ulimit -a

Willy

Re: How to produce a core

[gshan]

Willy Tarreau wrote:
> On Thu, May 24, 2007 at 11:28:15AM +0800, gshan wrote:
>   
>> This morning, I tried command "kill -7 [pid]" but didn't see the core 
>> file. Anybody has ideas?
>>     
>
> do the following before starting your program :
>
> # ulimit -c unlimited
>
> You can check before and after that the core size changed from 0 to
> "unlimited" :
>
> # ulimit -a
>
> Willy
>
>   
Willy,

Thank you very much. The command "kill -7 [pid]" really works with 
"ulimit -c unlimited"

# /bin/sh                                   
# ps
PID   USER     COMMAND
    1 0        init 
    2 0        [ksoftirqd/0]
    3 0        [desched/0]
    4 0        [events/0]
    5 0        [khelper]
   10 0        [kthread]
   31 0        [kblockd/0]
   60 0        [pdflush]
   61 0        [pdflush]
   63 0        [aio/0]
   62 0        [kswapd0]
   64 0        [jfsIO]
   65 0        [jfsCommit]
   66 0        [jfsSync]
   67 0        [xfslogd/0]
   68 0        [xfsdatad/0]
   69 0        [xfsbufd]
  706 0        [mtdblockd]
  730 0        -sh
  788 0        /bin/sh
  789 0        ps
# ulimit -c unlimited
# kill -7 788
Bus error (core dumped)
# ls -al
drwxr-xr-x   12 0        0               0 Jan  1 00:55 .
drwxr-xr-x   12 0        0               0 Jan  1 00:55 ..
drwxr-xr-x    2 1000     1000            0 Jan  1 00:00 bin
-rw-------    1 0        0          417792 Jan  1 00:55 
core                                       <<< Here is the corefile
drwxr-xr-x    2 0        0               0 Jan  1 00:00 dev
drwxr-xr-x    3 0        0               0 Jan  1 00:00 etc
lrwxrwxrwx    1 0        0              12 Jan  1 00:00 init -> /bin/busybox
drwxr-xr-x    2 0        0               0 Jan  1 00:00 lib
drwxr-xr-x    2 0        0               0 Jan  1 00:00 misc
dr-xr-xr-x   32 0        0               0 Jan  1 00:00 proc
drwx------    2 0        0               0 Jan  1 00:00 root
drwxr-xr-x    2 0        0               0 Jan  1 00:00 sbin
drwxr-xr-x    2 0        0               0 Jan  1 00:00 sys
drwxr-xr-x    4 0        0               0 Jan  1 00:00 usr
#

Thanks,
Gavin