The PKI Services daemon supports an installation-provided exit routine for automatic renewal processing. An exit routine can be written to provide additional automatic renewal criteria, and to capture the renewed certificate for further processing. If you choose to implement this exit routine, it must be a UNIX executable program residing in a file system, with appropriate permission assigned. The PKI Services daemon identifies the exit routine as the program specified by the value of the _PKISERV_EXIT environment variable in the pkiserv.envars file. The value specified is limited to a maximum of 256 characters. The exit routine is invoked by the PKI Services daemon using standard UNIX parameters (that is, argc and argv[]). The exit routine communicates its results back to the PKI Services daemon by way of a return code. The exit routine is called for preprocessing and post-processing before and after automatic certificate renewal processing. Unlike the PKI Services CGI exit routines, messages written to either STDOUT or STDERR do not appear in either the Web server or PKI Services daemon logs. If you want to write messages in the exit program, you need to open a file and write messages to that file. The sample exit routine provided in /usr/lpp/pkiserv/samples/pkiexit.c illustrates writing messages to a file in both the preprocessing and post-processing exit functions.