6 accesslog - Access logger for ashd(7)
10 *accesslog* [*-hFaeL*] [*-f* 'FORMAT'] [*-p* 'PIDFILE'] 'OUTFILE' 'CHILD' ['ARGS'...]
12 *accesslog* *-P* 'LOGFILE'
17 The *accesslog* handler starts a single child handler which it passes
18 all requests it receives, but also logs information about every such
19 request to 'OUTFILE'. As for the format of the log records, see the
20 FORMAT section, below.
22 *accesslog* is a persistent handler, as defined in *ashd*(7), and the
23 specified child handler must also be a persistent handler.
25 If 'OUTFILE' is `-`, log records will be written on standard
26 output. Otherwise, the specified filename is opened in append mode and
27 kept open for as long as *accesslog* runs. SIGHUP can be sent to
28 *accesslog* in order to get it to reopen the log file, which can be
29 useful e.g. for log rotation.
31 If the child handler exits, *accesslog* exits as well.
33 Normally, *accesslog* locks the logfile using *fcntl*(2) to ensure
34 that only one process writes to a logfile at any time. The *-L* switch
35 can be used to override that behavior to let several processes share a
36 logfile, or to use logfiles that cannot be locked for some reason.
43 Print a brief help message to standard output and exit.
47 Do not flush the log file buffers for each log record. (This
48 refers to the internal buffers, not the filesystem buffers.)
52 Use the specified 'FORMAT' string instead of the default log
53 record format. See the FORMAT section, below, for a
54 description of the 'FORMAT' string. See also the *-e* option.
58 Write the PID of the *accesslog* process to
59 'PIDFILE'. 'PIDFILE' may be `-`, in which case the string
60 "`.pid`" is appended to the log file name and used instead.
64 Try to emulate the Apache "combined" log format as closely as
65 possible. Currently, the remote user, identd user, status code
66 and number of sent bytes in Apache's combined format are
67 replaced with dashes. Effectively, the following format string
71 %A - - [%{%d/%b/%Y:%H:%M:%S %z}t] "%m %u %v" %c %o "%R" "%G"
76 Make extended log data available. This option makes
77 *accesslog* run in a different mode where it looks at not only
78 the request, but also the (entire) response, which requires
79 quite a bit more CPU time per request. However, some log items
80 are only available in this mode; these have been marked as
81 such under the FORMAT section, below.
85 Do not attempt to lock the logfile. Note that this switch
86 conflicts with the use of the *-P* option.
90 Makes *accesslog* fetch the PID of the process currently
91 holding the lock on 'LOGFILE', write that to standard output,
92 and then exit. No further command-line arguments are
93 processed. This option is useful for sending SIGHUP to
94 accesslog when rotating logfiles without having to use a PID
100 The log record format is specified with the *-f* option described
101 above. The format string is used as a template and certain fields are
102 expanded. Characters in the format string not matching such fields are
103 output as they are. A field is specified as a percent sign, followed
104 by an optional argument enclosed in braces, followed by a single
105 character specifying the item to log.
107 By default, the following format string is used:
110 %{%Y-%m-%d %H:%M:%S}t %m %u %A "%G"
113 The following log items are currently specified:
117 Expands into the HTTP header named by 'HEADER'. If the
118 specified header does not exist in the request, *%h* expands
123 Expands into the entire raw URL part of the request.
127 Expands into the raw URL part of the request, with any query
128 string removed if present.
132 Expands into the HTTP method.
136 Expands into the HTTP version string.
140 Expands into the current rest string.
144 Expands into the current time, in RFC822 format, unless there
145 is an argument present, in which case the argument is used as
146 a format string to *strftime*(3). The time is expressed in the
151 As for *%t*, but UTC time is used instead.
155 Expands into the non-integral fraction of the second of the
156 current time, expressed in microseconds and padded with zeroes
157 to 6 digits. For example, *%{%H:%M:%S}t.%s* can be used to log
162 Expands into the `X-Ash-Address` header.
166 Expands into the `Host` header.
170 Expands into the `Referer` header.
174 Expands into the `User-Agent` header.
176 The following log items are only available when running in extended
177 mode, requested by the *-e* option, as described above. If unavailable
178 due to not running in extended mode, each of the log items below will
179 instead expand into a dash.
183 Expands into the HTTP status code of the response.
187 Expands into the number of bytes sent by the client as a
188 request-body. HTTP headers are not counted.
192 Expands into the number of bytes sent back by the handler, to
193 the client, as the response-body. HTTP headers are not
194 counted, and neither are overhead as part of any required
195 transfer-encoding, such as chunking.
199 Expands into the time it took for the handler to complete the
200 response, expressed as seconds with 6 decimals precision.
202 In any expanded field, any "unsafe" characters are escaped. Currently,
203 this means that double-quotes and backslashes are prepended with a
204 backslash, newlines and tabs are expressed as, respectively, `\n` and
205 `\t`, and any other byte less than 32 or greater than 127 is expressed
206 as `\xAA`, where `AA` is the hexadecimal representation of the byte.
213 Reopen the log file by name. If the log file name cannot be
214 re-opened, the old log file stream continues in use.
218 Fredrik Tolf <fredrik@dolda2000.com>