KUTIL_OPENLOG(3) Library Functions Manual KUTIL_OPENLOG(3)

kutil_openlog — configure log message sink

library “libkcgi”

#include <sys/types.h>
#include <stdarg.h>
#include <stdint.h>
#include <kcgi.h>

int
kutil_openlog(const char *file);

The () function configures output for the kutil_log(3) family of functions. By default, these functions log to stderr and inherit the initial output buffering behaviour (see setvbuf(3)).

If file is not NULL, () first redirects stderr to file. Then, regardless of whether file is NULL, the output buffering of the stream is set to line buffered.

CGI scripts invoking long-running child processes via fork(2) should use this function with a valid file as the web server might wait for all file descriptors to close before closing the request connection.

The kutil_openlog() function returns zero on failure (system error) and non-zero on success. If kutil_openlog() fails to re-open stderr, the output stream may no longer be operable: the caller should exit.

The kutil_openlog() function was written by Kristaps Dzonsons <kristaps@bsd.lv>.

In most situations, file is configured in the default log directory, which is not writable to the CGI process. Thus, file must be pre-created and be writable to the CGI process. Otherwise, kutil_openlog() will fail to create the file and exit with failure.

December 2, 2023 OpenBSD 7.4