On Mon, Jul 07, 2008 at 11:40:06AM +0200, Ehlers, Kolja wrote: > > I have a general question about bash programming since yet I am > not too familiar with it. The isrunning_tomcat() function in the > tomcat ocf keeps returning an error code. This is the function: > > if wget -O /dev/null $RESOURCE_STATUSURL 2>/dev/null; then > return $OCF_SUCCESS > fi > return $OCF_ERR_GENERIC > > The problem is the if condition keeps returning false. I just dont > get this part: > > wget -O /dev/null $RESOURCE_STATUSURL 2>/dev/null; > > What does especially the 2 mean? I know that wget tries to connect > to the statusurl, but the wget responds is directed to dev/null so > how can this be true or false?
The 2> part is redirecting file descriptor 2 (stderr) to /dev/null, which hides the status messages as well as any error messages. The actual file download is output to /dev/null as well (via -O). The return code is whatever wget exit()s to the system with. You can look at it in the shell with $?. e.g. $ true ; echo $? 0 $ false ; echo $? 1 So to test wget, you can work out what $RESOURCE_STATUSURL is, and then run: wget -O /dev/null http://whatever/the/status/url/is.jsp echo $? The 'echo $?' should output 0 if the service is available. Anything else will be evaluated as "false". _______________________________________________ Linux-HA mailing list [email protected] http://lists.linux-ha.org/mailman/listinfo/linux-ha See also: http://linux-ha.org/ReportingProblems
