1COAP-CLIENT(5) coap-client Manual COAP-CLIENT(5)
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6 coap-client - CoAP Client based on libcoap
7
9 coap-client [-a addr] [-b [num,]size] [-e text] [-f file] [-l loss] [-m
10 method] [-o file] [-p port] [-r] [-s duration] [-t type] [-v num] [-A
11 type] [-B seconds] [-K interval] [-N] [-O num,text] [-P addr[:port]]
12 [-T token] [-U] [[-k key] [-u user]] [[-c certfile] [-C cafile] [-R
13 root_cafile]] URI
14
16 coap-client is a CoAP client to communicate with 6LoWPAN devices via
17 the protocol CoAP (RFC 7252) using the URI given as argument on the
18 command line. The URI must have the scheme coap, coap+tcp, coaps or
19 coaps+tcp. coaps and coaps+tcp are only supported when coap-client is
20 built with support for secure (D)TLS communication.
21 If coaps or coap+tcp is being used, provided the CoAP server supports
23 PKI and is configured with a Certificate and Private Key, the
24 coap-client does not need to have a Pre-Shared Key (-k) or Certificate
25 (-c) configured.
26 The URI’s host part may be a DNS name or a literal IP address. Note
28 that, for IPv6 address references, angle brackets are required (c.f.
29 EXAMPLES).
30
32 -a addr
33 The local address of the interface that has to be used.
34 -b [num,]size
36 The block size to be used in GET/PUT/POST requests (value must be a
37 multiple of 16 not larger than 1024 as libcoap uses a fixed maximum
38 PDU size of 1400 bytes). If num is present, the request chain will
39 start at block num. When the server includes a Block2 option in its
40 response to a GET request, coap-client will automatically retrieve
41 the subsequent block from the server until there are no more
42 outstanding blocks for the requested content.
43 -e text
45 Include text as payload (use percent-encoding for non-ASCII
46 characters).
47 -f file
49 File to send with PUT/POST (use - for STDIN).
50 -l list
52 Fail to send some datagrams specified by a comma separated list of
53 numbers or number ranges (debugging only).
54 -l loss%
56 Randomly failed to send datagams with the specified probability -
57 100% all datagrams, 0% no datagrams (debugging only).
58 -m method
60 The request method for action (get|put|post|delete), default is
61 get. (Note that the string passed to -m is compared
62 case-insensitive.)
63 -o file
65 A filename to store data retrieved with GET.
66 -p port
68 The port to listen on.
69 -r
71 Use reliable protocol (TCP or TLS).
72 -s duration
74 Subscribe to / observe the resource specified by URI for the given
75 duration in seconds.
76 -t type
78 Content format for given resource for PUT/POST. type must be
79 either a numeric value reflecting a valid CoAP content format or a
80 string describing a registered format. The following registered
81 content format descriptors are supported, with alternative
82 shortcuts given in parentheses:
83 text/plain (plain)
85 application/link-format (link, link-format)
86 application/xml (xml)
87 application/octet-stream (binary, octet-stream)
88 application/exi (exi)
89 application/json (json)
90 application/cbor (cbor)
91 -v num
93 The verbosity level to use (default 3, maximum is 9). Above 7,
94 there is increased verbosity in GnuTLS and OpenSSL logging.
95 -A type
97 Accepted media type. type must be either a numeric value
98 reflecting a valid CoAP content format or a string that specifies a
99 registered format as described for option -t.
100 -B seconds
102 Break operation after waiting given seconds (default is 90).
103 -K interval
105 Send a ping after interval seconds of inactivity. If not specified
106 (or 0), keep-alive is disabled (default).
107 -N
109 Send NON-confirmable message. If option -N is not specified, a
110 confirmable message will be sent.
111 -O num,text
113 Add option num with contents of text to the request. If the text
114 begins with 0x, then the hex text is converted to binary data.
115 -P addr[:port]
117 Address (and port) for proxy to use (automatically adds Proxy-Uri
118 option to request).
119 -T token
121 Include the token to the request.
122 -U
124 Never include Uri-Host or Uri-Port options.
125
127 (If supported by underlying (D)TLS library)
128 -k key
130 Pre-shared key for the specified user (-u option also required).
131 -u user
133 User identity for pre-shared key mode (-k option also required).
134
136 (If supported by underlying (D)TLS library)
137 -c certfile
139 Use the specified PEM file which contains the CERTIFICATE and
140 PRIVATE KEY information.
141 -C cafile
143 PEM file containing the CA Certificate that was used to sign the
144 certfile defined using -c certfile. This will trigger the
145 validation of the server certificate. If certfile is self-signed
146 (as defined by -c certfile), then you need to have on the command
147 line the same filename for both the certfile and cafile (as in -c
148 certfile -C certfile) to trigger validation.
149 -R root_cafile
151 PEM file containing the set of trusted root CAs that are to be used
152 to validate the server certificate. The -C cafile does not have to
153 be in this list and is "trusted" for the verification.
154 Alternatively, this can point to a directory containing a set of CA
155 PEM files.
156
158 • Example
159 coap-client coap://coap.me
161 Query the resource / from server coap.me (using the GET method).
163 • Example
165 coap-client -m get coap://[::1]/
167 Query the resource / on localhost using the GET method to get back the
169 summary defined attributes.
170 • Example
172 coap-client -m get coap://[::1]/.well-known/core
174 Query on the resource .well-known/core on localhost to get back a list
176 of the known resources along with their attribute definitions.
177 • Example
179 echo -n "mode=on" | coap-client -m put \
181 coap://[2001:db8:c001:f00d:221:2eff:ff00:2704]:5683/actuators/leds?color=r -f-
182 Send text mode=on to resource actuators/leds?color=r on the endpoint
184 with address 2001:db8:c001:f00d:221:2eff:ff00:2704 and port 5683. Note
185 that the port 5683 is the default port and isn’t actually required in
186 this instance.
187 • Example
189 coap-client -m put coap://[fec0::3]/ck -T 3a -t binary -f to_upload
191 Put the contents of file to_upload with content type binary (i.e.
193 application/octet-stream) into resource ck on fec0::3 using a token of
194 3a via the PUT method.
195
197 There are no configuration files.
198
200 0
201 Success
202 1
204 Failure (syntax or usage error; configuration error; document
205 processing failure; unexpected error)
206
208 Please report bugs on the mailing list for libcoap:
209 libcoap-developers@lists.sourceforge.net
210
212 The libcoap project <libcoap-developers@lists.sourceforge.net>
213coap-client 4.2.1 01/26/2021 COAP-CLIENT(5)