Is there a way to add to OS X's install.log from within a shell script?

Question

Is there a way to add an entry to OS X's /var/log/install.log file from within a shell script?

Optimally the method wouldn't require root access as I don't think I'll have it.

The problem I'm having is I'm executing a shell script as part of an installation-check (p15 of Apple's Distribution Definition XML Schema) step from within an OS X installer package via the Javascript System.run() command (p30 of Apple's Installer Javascript Reference), but I can't see any output from that shell script.

I know the shell script is executing, because when I use the "logger" command from within the script, my log text appears inside /var/log/system.log. But in order to get a complete picture of what's going on, I'd need to merge it by hand with /var/log/install.log, which is where the general output of the installer, and any Javascript logging I do, ends up.

Any help would be appreciated. I've tried using the "logger" command's -f flag to use /var/log/install.log, e.g.

logger -f /var/log/install.log sometext

...but no dice; sometext still gets added to /var/log/system.log.

Answer 1

A little late, but just had the same problem and was able to add logs to install.log from AppleScript using logger with the LOG_INSTALL facility:

logger -p 'install.error' "My error message"