Open Radar

 
Summary:
The public ASL API uses a set formatting for the message and time. However the private portions of the ASL API actually do support different formatting. see: asl_format_message from http://www.opensource.apple.com/source/Libc/Libc-825.26/gen/asl_msg.h

The formatting options are extended up to the adding of a file (so certain files can have particular formatting). see: asl_add_output from http://www.opensource.apple.com/source/Libc/Libc-825.26/gen/asl_private.h

The issue here is the public API for adding a file does not accept formatting options and instead opts to use a specific options. see: asl_add_log_file from http://www.opensource.apple.com/source/Libc/Libc-825.26/gen/asl.c It simply calls asl_add_output with ASL_MSG_FMT_STD, ASL_TIME_FMT_LCL for the formatting.

Comparing this with the command line tool equivalent (Syslog), it supports formatting through the -F option. see:  -F format in http://developer.apple.com/library/mac/#documentation/Darwin/Reference/ManPages/man1/syslog.1.html

Workaround:
The current workaround is to either live with the fixed formatting when using the API, run the Syslog program, or to access the private API function asl_add_output.

Suggested Solution:
To make the asl_add_output function public, or to be able to change the formatting somehow.