-C - Load configuration file specified.\n\
--config-file  -C - Load configuration file specified.\n\ --configuration-directory\n\ --config-dir      - Load <dir>
static void usage(const char *program_name, int ret, const char *prefix){  Vstr_base *out = vstr_make_base(NULL);  if (!out)    errno = ENOMEM, err(EXIT_FAILURE, "usage");  vstr_add_fmt(out, 0, "%s\n\ Format: %s [options] <dir>\n\  Daemon options\n\    --configuration-file\n\                   -C - Load configuration file specified.\n\    --configuration-data-daemon\n\                      - Parse configuration given in the\n\                        org.and.daemon-conf-1.0 namespace.\n\    --daemon          - Toggle becoming a daemon%s.\n\    --chroot          - Change root.\n\    --drop-privs      - Toggle droping privilages%s.\n\    --priv-uid        - Drop privilages to this uid.\n\    --priv-gid        - Drop privilages to this gid.\n\    --pid-file        - Log pid to file.\n\    --cntl-file       - Create control file.\n\    --accept-filter-file\n\                      - Load Linux Socket Filter code for accept().\n\    --processes       - Number of processes to use (default: 1).\n\    --debug -d        - Raise debug level (can be used upto 3 times).\n\    --host -H         - IPv4 address to bind (default: \"all\").\n\    --help -h         - Print this message.\n\    --max-connections\n\                   -M - Max connections allowed (0 = no limit).\n\    --nagle -n        - Toggle usage of nagle TCP option%s.\n\    --port -P         - Port to bind to.\n\    --idle-timeout -t - Timeout (usecs) for connections that are idle.\n\    --defer-accept    - Time to defer dataless connections (default: 8s)\n\    --version -V      - Print the version string.\n\\n\  HTTPD options\n\    --configuration-data-httpd\n\                      - Parse configuration given in the\n\                        org.and.httpd-conf-main-1.0 namespace.\n\    --mmap            - Toggle use of mmap() to load files%s.\n\    --sendfile        - Toggle use of sendfile() to load files%s.\n\    --keep-alive      - Toggle use of Keep-Alive handling%s.\n\    --keep-alive-1.0  - Toggle use of Keep-Alive handling for HTTP/1.0%s.\n\    --virtual-hosts\n\    --vhosts          - Toggle use of directory virtual hostnames%s.\n\    --range           - Toggle use of partial responces%s.\n\    --range-1.0       - Toggle use of partial responces for HTTP/1.0%s.\n\    --public-only     - Toggle use of public only privilages%s.\n\    --directory-filename\n\    --dir-filename    - Filename to use when requesting directories.\n\    --server-name     - Contents of server header used in replies.\n\    --gzip-content-replacement\n\                      - Toggle use of gzip content replacement%s.\n\    --mime-types-main - Main mime types filename (default: /etc/mime.types).\n\    --mime-types-xtra - Additional mime types filename.\n\    --error-406       - Toggle sending 406 responses%s.\n\    --canonize-host   - Strip leading 'www.', strip trailing '.'%s.\n\    --error-host-400  - Give an 400 error for a bad host%s.\n\    --check-host      - Whether we check host headers at all%s.\n\    --unspecified-hostname\n\                      - Used for req with no Host header (default is hostname).\n\    --max-header-sz   - Max size of http header (0 = no limit).\n\",               prefix, program_name,               opt_def_toggle(FALSE), opt_def_toggle(FALSE),               opt_def_toggle(EVNT_CONF_NAGLE),               opt_def_toggle(HTTPD_CONF_USE_MMAP),               opt_def_toggle(HTTPD_CONF_USE_SENDFILE),               opt_def_toggle(HTTPD_CONF_USE_KEEPA),               opt_def_toggle(HTTPD_CONF_USE_KEEPA_1_0),               opt_def_toggle(HTTPD_CONF_USE_VHOSTS_NAME),               opt_def_toggle(HTTPD_CONF_USE_RANGE),               opt_def_toggle(HTTPD_CONF_USE_RANGE_1_0),               opt_def_toggle(HTTPD_CONF_USE_PUBLIC_ONLY),               opt_def_toggle(HTTPD_CONF_USE_ENC_CONTENT_REPLACEMENT),               opt_def_toggle(HTTPD_CONF_USE_ERR_406),               opt_def_toggle(HTTPD_CONF_USE_CANONIZE_HOST),               opt_def_toggle(HTTPD_CONF_USE_HOST_ERR_400),               opt_def_toggle(HTTPD_CONF_USE_HOST_ERR_CHK));  if (io_put_all(out, ret ? STDERR_FILENO : STDOUT_FILENO) == IO_FAIL)    err(EXIT_FAILURE, "write");    exit (ret);}