1YAWS(1) User Commands YAWS(1)
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6 yaws - yet another webserver
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9 yaws [OPTIONS]
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12 Yaws is fast lightweight webserver. It can run as daemon or in interac‐
13 tive mode where it is possible to directly interact with the webserver.
14 Yaws is particularly good at generating dynamic content. See the user
15 docs for more information on that topic.
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19 -i | --interactive
20 Interactive mode. This will start yaws in interactive mode with
21 an erlang prompt. All error_logger messages will be written to
22 the tty as well in this mode. Use this when developing yaws
23 code.
24 -w | --winteractive
26 Cygwin inteactive mode (werl)
27 -D | --daemon
29 Daemon mode. This will start yaws as a daemon.
30 --heart
32 This will cause the yaws system to be automatically restarted in
33 case it should crash. This switch also requires the --daemon
34 switch to be present.
35 --heart-restart=C,T
37 This controls the number of restarts in a given time period that
38 heart tolerates before refusing to restart Yaws. By default,
39 heart allows up to 5 restarts within a 60 second period before
40 refusing to restart Yaws again. This option allows up to C
41 restarts in T seconds instead. To allow infinite restarts, set
42 both C and T to 0. This switch automatically enables the --heart
43 switch.
44 --debug
46 Debug mode. This will produce some auxiliary error output for
47 some error conditions. It will also start the otp sasl lib for
48 additional error printouts.
49 --nodebug
51 Non-debug mode. This is useful for running interactively via the
52 -i option but without incurring the performance penalties of
53 debug mode.
54 --conf file
57 Use a different configuration file than the default. The default
58 configuration file when running as root is /etc/yaws/yaws.conf.
59 When running as a non priviliged user, yaws will search for its
60 configuration file in the following order. First in
61 $HOME/yaws.conf, then in ./yaws.conf and finally in
62 /etc/yaws/yaws.conf
63 --runmod module
65 Tells yaws to call module:start/0 at startup. This makes it pos‐
66 sible to startup user specific applications together with yaws.
67 --pa path
70 Add path to the yaws system search path
71 --tracetraf
74 Traffic trace mode. All traffic will be written to a trace file
75 called trace.traffic in the log directory.
76 --tracehttp
79 HTTP trace mode. All HTTP messages will be written to a trace
80 file called trace.http in the log directory.
81 --traceout
84 When yaws is put into trace mode using either --tracetraf or
85 --tracehttp, traces are written to files. If we provide the
86 --traceout flag, the trace will also be written to stdout.
87 --trace
90 Sames as --tracetraf --traceout. I.e. trace everything and write
91 to stdout.
92 --mnesiadir dir
95 Start Mnesia in directory <dir>
96 --sname xxx
99 Start yaws as a distributed erlang node with name <xxx> using
100 the unqualified hostname as nodename postfix
101 --disable-kpoll
104 By default, yaws starts erlang with +K true. This flag reverses
105 that.
106 --name xxx
109 Start yaws as a distributed erlang node with name <xxx> using
110 the fully qualified hostname as nodename postfix
111 --proto_dist Mod
114 Use module Mod for erlang distribution. This is typically only
115 used when we want to run erlang distribution over SSL.
116 --erlarg STRING
119 Pass STRING as an additional argument to the "erl" program. If
120 STRING comprises multiple words, you must quote it so that your
121 shell passes it to yaws as a single argument. If STRING contains
122 any single quote characters, you must quote each of them as
123 well. For example, to pass the option -env NAME O'Keeffe to
124 "erl" from a Bourne-compatible shell:
125 --erlarg "-env NAME O\'Keeffe"
127 --id ID
130 This flag sets the id. If we're starting a daemon (or an inter‐
131 active system) it gives the Yaws server the identity ID. This
132 means that the server will write all internal files into the
133 directory $HOME/.yaws/yaws/ID.
134 Yaws also creates a file called ${VARDIR}/run/yaws/ctl-${ID}
136 which contains the portnumber the daemon is listening on for
137 control request by the control command such as "yaws --hup" etc.
138 If we're invoking a control command which should perform some
140 control function on the daemon, we may have to give the --id
141 flag also to the control command. If we don't do this the con‐
142 trol command may interact with the wrong daemon due to finding
143 the wrong "ctl" file.
144 The daemon may also optionally specify the "id" in the yaws.conf
146 configuration file.
147 --umask MASK
150 Set the umask for the daemon to MASK.
151
154 The following list of options are are used to control the daemon from
155 the "outside" while it is running.
156 --hup [--id ID]
159 HUP the daemon. This forces the daemon to reread the configura‐
160 tion file. It also makes the daemon empty all its internal con‐
161 tent caches. Hence when updating the doc root, HUPing the dae‐
162 mon is the fastest way to see the content updates.
163 --stop [--id id]
165 Stop the daemon (called id)
166 --ls Lists current ids and status of all yaws servers on localhost.
168 In practice this amounts to a listdir in $HOME/.yaws/yaws - and
169 check whether the different systems who has created files there
170 are alive.
171 --status [--id id]
173 Query a running yaws daemon for its status, and print it.
174 --stats [--id id]
176 Query a running yaws daemon for its statistics, and print it.
177 --load Modules [--id id]
179 Try to (re)load erlang modules into a running daemon. This is
180 useful after modifying appmods or modules used by scripts.
181 --debug-dump [--id id]
184 Produce a debug dump on stdout. In particular this code lists
185 what we refer to as suspicious processes. I.e. processes that
186 might be hanging or processes that are "large" - hardcoded to
187 40k words.
188 --ctltrace [--id ID] http | traffic | off
191 Control the trace capabilities of a running yaws daemon. If the
192 http or traffic option is given, the daemon will write a log for
193 debug purposes into the logdir.
194 --wait-started[=T] [--id ID]
197 Waits at most 5 seconds for the server to start. Exits with 0 if
198 server is running, 1 otherwise. Typically useful in test
199 scripts. The default 5 seconds can be modified by appending =T
200 to the option, where T is the desired number of seconds to wait
201 for the server to start.
202
205 --check YawsFile [IncDirs ....]
206 Test compile a `.yaws' file. Useful in Makefiles when we want to
207 ensure that all .yaws files are syntactically correct
208 --version
210 output version information and exit
211
214 HOME Is used to determine where we write the temporary files. By
215 default all tmp files end up in $HOME/.yaws. This includes the
216 JIT files that are the result of processed .yaws files and also
217 the so called control file that is used by the daemon to write
218 the port number to which it is listening for control commands
219 such as "yaws --status"
220 Thus HOME is the handle we use in the control commands to find
222 the control file so that we know where to connect to.
223 YAWSHOME
226 Can be used to override the HOME variable. This is useful when
227 we for example are running yaws under port binding programs such
228 as authpriv.
229 It's useful by distros that don't want Yaws to write any files
231 ever in the HOME directory of root.
232
237 Written by Claes Wikstrom
238
240 yaws.conf(5) erl(1)
241 YAWS(1)