CODEWITHSUNDEEP
c++linuxsyslogrsyslog
suresh
suresh

Reputation: 1109

How to configure syslog so that an applications log goes to a specific file

I have an application myapp which should send log files only to /var/log/myapp.log. myapp is written in C++. The following sample code, sends the logs to /var/log/syslog only. My os is Linux - Ubuntu 12.04 - to be specific. I also found that my machine has rsyslog than syslog installed.

#include <stdio.h>
#include <unistd.h>
#include <syslog.h>

int main(void) {
    openlog("myapp", LOG_PID|LOG_CONS, LOG_USER);
    syslog(LOG_INFO, "abc 10");
    closelog();
    return 0;
}

Upvotes: 13

Views: 51522

Answers (3)

YanDatsiuk
YanDatsiuk

Reputation: 1963

This worked for me: OS: Ubuntu 20.04

  1. Add to the config /etc/rsyslog.conf

:programname,contains,"myapp" /var/log/myapp.log

  1. service rsyslog restart

Upvotes: 2

frankscitech
frankscitech

Reputation: 81

If your Ubuntu is working with rsyslog, you need to find the configuration file /etc/rsyslog.conf and modify it.

$ echo "if \$programname == 'myapp' then /var/log/myapp.log \n& ~" >> /etc/rsyslog.conf

Then you restart the utility:

$ sudo service rsyslog restart

And run your programm:

$ ./myapp

Check your log:

$ cat /var/log/myapp.log 
Apr  8 14:01:51 myusername myapp[21508]: abc 10

Upvotes: 2

lupz
lupz

Reputation: 3638

According to the syslog(3) manpage, the first parameter for openlog() sets a prefix for log messages, not a filename. You can use a facility like LOG_LOCAL0 to flag your output and then configure syslogd using /etc/syslog.conf to send those logs to the file of your desire.

Upvotes: 12

Related Questions