1cu(1) General Commands Manual cu(1)
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6 cu - Call up another system
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9 cu [ options ] [ system | phone | "dir" ]
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12 The cu command is used to call up another system and act as a dial in
13 terminal. It can also do simple file transfers with no error checking.
14 cu takes a single argument, besides the options. If the argument is
16 the string "dir" cu will make a direct connection to the port. This
17 may only be used by users with write access to the port, as it permits
18 reprogramming the modem.
19 Otherwise, if the argument begins with a digit, it is taken to be a
21 phone number to call. Otherwise, it is taken to be the name of a sys‐
22 tem to call. The -z or --system option may be used to name a system
23 beginning with a digit, and the -c or --phone option may be used to
24 name a phone number that does not begin with a digit.
25 cu locates a port to use in the UUCP configuration files. If a simple
27 system name is given, it will select a port appropriate for that sys‐
28 tem. The -p, --port, -l, --line, -s and --speed options may be used to
29 control the port selection.
30 When a connection is made to the remote system, cu forks into two pro‐
32 cesses. One reads from the port and writes to the terminal, while the
33 other reads from the terminal and writes to the port.
34 cu provides several commands that may be used during the conversation.
36 The commands all begin with an escape character, initially ~ (tilde).
37 The escape character is only recognized at the beginning of a line. To
38 send an escape character to the remote system at the start of a line,
39 it must be entered twice. All commands are either a single character
40 or a word beginning with % (percent sign).
41 cu recognizes the following commands:
43 ~. Terminate the conversation.
46 ~! command
48 Run command in a shell. If command is empty, starts up a shell.
49 ~$ command
51 Run command, sending the standard output to the remote system.
52 ~| command
54 Run command, taking the standard input from the remote system.
55 ~+ command
57 Run command, taking the standard input from the remote system and
58 sending the standard output to the remote system.
59 ~#, ~%break
61 Send a break signal, if possible.
62 ~c directory, ~%cd directory
64 Change the local directory.
65 ~> file
67 Send a file to the remote system. This just dumps the file over
68 the communication line. It is assumed that the remote system is
69 expecting it.
70 ~< Receive a file from the remote system. This prompts for the local
72 file name and for the remote command to execute to begin the file
73 transfer. It continues accepting data until the contents of the
74 eofread variable are seen.
75 ~p from to, ~%put from to
77 Send a file to a remote Unix system. This runs the appropriate
78 commands on the remote system.
79 ~t from to, ~%take from to
81 Retrieve a file from a remote Unix system. This runs the appro‐
82 priate commands on the remote system.
83 ~s variable value
85 Set a cu variable to the given value. If value is not given, the
86 variable is set to true.
87 ~! variable
89 Set a cu variable to false.
90 ~z Suspend the cu session. This is only supported on some systems.
92 On systems for which ^Z may be used to suspend a job, ~^Z will
93 also suspend the session.
94 ~%nostop
96 Turn off XON/XOFF handling.
97 ~%stop
99 Turn on XON/XOFF handling.
100 ~v List all the variables and their values.
102 ~? List all commands.
104 cu also supports several variables. They may be listed with the
106 ~v command, and set with the ~s or ~! commands.
107 escape
110 The escape character. Initially ~ (tilde).
111 delay
113 If this variable is true, cu will delay for a second after recog‐
114 nizing the escape character before printing the name of the local
115 system. The default is true.
116 eol The list of characters which are considered to finish a line. The
118 escape character is only recognized after one of these is seen.
119 The default is carriage return, ^U, ^C, ^O, ^D, ^S, ^Q, ^R.
120 binary
122 Whether to transfer binary data when sending a file. If this is
123 false, then newlines in the file being sent are converted to car‐
124 riage returns. The default is false.
125 binary-prefix
127 A string used before sending a binary character in a file trans‐
128 fer, if the binary variable is true. The default is ^V.
129 echo-check
131 Whether to check file transfers by examining what the remote sys‐
132 tem echoes back. This probably doesn't work very well. The
133 default is false.
134 echonl
136 The character to look for after sending each line in a file. The
137 default is carriage return.
138 timeout
140 The timeout to use, in seconds, when looking for a character,
141 either when doing echo checking or when looking for the echonl
142 character. The default is 30.
143 kill The character to use delete a line if the echo check fails. The
145 default is ^U.
146 resend
148 The number of times to resend a line if the echo check continues
149 to fail. The default is 10.
150 eofwrite
152 The string to write after sending a file with the ~> command. The
153 default is ^D.
154 eofread
156 The string to look for when receiving a file with the ~< command.
157 The default is $, which is intended to be a typical shell prompt.
158 verbose
160 Whether to print accumulated information during a file transfer.
161 The default is true.
162
164 The following options may be given to cu.
165 -e, --parity=even
167 Use even parity.
168 -o, --parity=odd
170 Use odd parity.
171 --parity=none
173 Use no parity. No parity is also used if both -e and -o are
174 given.
175 -h, --halfduplex
177 Echo characters locally (half-duplex mode).
178 --nostop
180 Turn off XON/XOFF handling (it is on by default).
181 -E char, --escape char
183 Set the escape character. Initially ~ (tilde). To eliminate the
184 escape character, use -E ''.
185 -z system, --system system
187 The system to call.
188 -c phone-number, --phone phone-number
190 The phone number to call.
191 -p port, --port port
193 Name the port to use.
194 -a port
196 Equivalent to --port port.
197 -l line, --line line
199 Name the line to use by giving a device name. This may be used to
200 dial out on ports that are not listed in the UUCP configuration
201 files. Write access to the device is required.
202 -s speed, --speed speed
204 The speed (baud rate) to use.
205 -# Where # is a number, equivalent to --speed #.
207 -n, --prompt
209 Prompt for the phone number to use.
210 -d Enter debugging mode. Equivalent to --debug all.
212 -x type, --debug type
214 Turn on particular debugging types. The following types are rec‐
215 ognized: abnormal, chat, handshake, uucp-proto, proto, port, con‐
216 fig, spooldir, execute, incoming, outgoing. Only abnormal, chat,
217 handshake, port, config, incoming and outgoing are meaningful for
218 cu.
219 Multiple types may be given, separated by commas, and the --debug
221 option may appear multiple times. A number may also be given,
222 which will turn on that many types from the foregoing list; for
223 example, --debug 2 is equivalent to --debug abnormal,chat.
224 --debug all may be used to turn on all debugging options.
225 -I file, --config file
227 Set configuration file to use. This option may not be available,
228 depending upon how cu was compiled.
229 -v, --version
231 Report version information and exit.
232 --help
234 Print a help message and exit.
235
237 This program does not work very well.
238
240 Ian Lance Taylor <ian@airs.com>
241 Taylor UUCP 1.07 cu(1)