2

How do I change the log path of syslog daemon during runtime? My goal is to rotate log file every filesize or date, but I don't have logrotate in QNX/POSIX.

Do I just do an edit and hope that the syslogd checks the .conf file everytime, or is there any other workaround? Thanks.

Clarification: It has to be done in C or C++, not in script and console command line, for portabality issues.

freonix
  • 1,605
  • 3
  • 22
  • 35

3 Answers3

2

Find the pid of syslogd. Let's say it's 123. Then, after you've finished your edit, on the command line, type one of these:

kill -HUP 123
kill -1 123
Bill Evans at Mariposa
  • 3,590
  • 1
  • 18
  • 22
  • Thanks, but I'm lookinng for something that can be executed inside my code during runtime – freonix May 13 '11 at 02:03
  • You can use the `kill(2)` syscall, or use `system(3)`. No way around having to send that signal to syslogd or restarting it. – Bruno Rohée May 13 '11 at 02:30
  • I suppose Bill wants me to restart it once I kil the PID? – freonix May 13 '11 at 03:05
  • No. The "kill" command sends a signal. Whether that kills the process depends on (a) which signal you send, and (b) what the program does with it. Some signals will kill any program they encounter. HUP isn't one of those. Many programs, including syslogd, use that signal as advice that the configuration file has changed and needs to be re-read. No need to restart syslogd, because the HUP signal doesn't cause syslogd to exit or abort. – Bill Evans at Mariposa May 14 '11 at 22:46
  • Oh. And. You can use the kill() library call from inside your program. – Bill Evans at Mariposa May 14 '11 at 22:53
1

Answer based on some solution found on web, and also based on @bills answer, modified to suit QNX environment.

Perform a system call for slay syslogd and perform edit to syslog.conf and system call to syslogd again.

QNX does not supply logrotate, otherwise other than the above answer, install third party logging is another workaround, though does not fit my purpose.

update: After some digging, QNX provides a alternative called slogger within Neutrino OS. I'll be voting for this as an answer as it is catering to QNX system

freonix
  • 1,605
  • 3
  • 22
  • 35
  • 2
    Since you are new here are some pointers: vote up Bill's answer - it led you to the solution. Optionally - consider accepting his answer and putting the details of your solution as EDIT in the answer itself. (this may be subjective opinion). Finally, if you refer to other solutions on the web, link to them. (All this rant is not a critique, just pointers...) – Unreason May 16 '11 at 08:31
0

Sounds to me you're best helped with porting newsyslog to your platform.

Mel
  • 6,077
  • 1
  • 15
  • 12
  • Thanks a lot, but again, looking for a solution which performs inside code. Sorry if I didn't clarify clearly before. – freonix May 13 '11 at 02:04