1CONE(1) Cone: COnsole Newsreader And E CONE(1)
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6 cone - Read and send E-mail messages
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9 cone [-r] [-c directory]
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12 Cone is a console newsreader and E-mail. It is an interactive program
13 for reading and sending E-mail messages. Cone is designed to be
14 intuitive and easy to learn. Starting Cone for the first time displays
15 two links: one for the default system mailbox, and a second link to a
16 quick online tutorial. The online tutorial provides a brief overview of
17 using Cone for reading and sending E-mail.
18 Pressing Q on most screens exits Cone. Cone tries to gracefully log
20 out and shut down all server connections. If Cone cannot log out of a
21 remote server because the remote server is down, press CTRL-C (after Q
22 to terminate Cone).
23 Use CTRL-Z to temporarily suspend Cone and drop back to the shell
25 prompt. Cone remains suspended in the background, and may be restarted
26 by using the shell´s fg command.
27 Note
29 Connections to remote mail servers may be disconnected for
30 inactivity if Cone remains suspended for a prolonged period of
31 time. When suspended, Cone cannot maintain any active connections
32 to remote mail servers.
33 The -c option names a directory where Cone saves its configuration
35 files, and defaults to $HOME/.cone. The configuration directory will be
36 created, if necessary.
37 The -r option recovers a backup copy of Cone´s configuration file. This
39 option is primarily used when remote configuration is enabled, but the
40 folder that contains Cone´s configuration on a remote server was
41 deleted, or is not available. In all cases, Cone makes a daily local
42 configuration file backup. The -r option searches for local
43 configuration file backups, and offers an option to restore the backup
44 copy.
45 Reading local mail with Cone
47 Cone reads local mail from either maildirs (the preferred format) or
48 mailbox files (or "mboxes"). When mboxes are used, Cone does not read
49 the system mailbox file directly (usually /var/spool/something). All
50 messages in the system mailbox are automatically moved to $HOME/Inbox,
51 which is then accessed as if it was the system mailbox. Starting Cone
52 for the first time on an mbox-based system automatically copies all
53 existing mail from the system mailbox file to $HOME/Inbox.
54 This is an intentional design choice. Normal user application cannot
56 create new files in /var/spool; all they can do is read the mailbox
57 file from /var/spool. Therefore, the only way to update the mailbox
58 file is by rewriting it from scratch (more or less). While the mailbox
59 file is in the process of being rewritten, if the Cone process is
60 interrupted, or killed, the resulted in a corrupted system mailbox.
61 There are way to minimize this vulnerability, but it cannot be
62 eliminated completely. Some Linux kernels use an “OOM killer” that may
63 terminate any process when the system memory is low. There is no way to
64 completely prevent corrupted system mailbox files on those kernels.
65 Cone uses an alternative way of updating mboxes. Cone updates mboxes
67 by creating a new mbox file separately, then replacing the original
68 mbox file with the new version. Unfortunately this cannot be done with
69 the system mailbox file, because of the restricted access rights on the
70 system spool directory. To solve this problem Cone automatically copies
71 the system mailbox file to $HOME/Inbox, each time the system mailbox
72 file is opened and whenever new mail is available.
73 Viewing MIME attachments
75 Cone displays text and simple HTML content by itself. Other kinds of
76 attachments may be viewed by using a helper script. Cone invokes a
77 helper script to open a MIME attachment. The helper script´s name is
78 “TYPE.SUBTYPE.filter”, where “TYPE” and “SUBTYPE” corresponds to the
79 MIME type and subtype, accordingly. Cone looks for helper scripts in
80 $HOME/.cone (or the directory specified by -c) and in /usr/share/cone.
81 For example, a helper script named “IMAGE.GIF.filter”, if installed, is
83 invoked to process image/gif MIME attachments.
84 Helper scripts
86 Cone runs each helper script twice:
87 TYPE.SUBTYPE.filter check type/subtype
89 When the first argument is “check”, the helper script should
91 terminate with a zero exit code if it is willing to process an
92 attachment whose MIME type is specified by the second argument. A
93 script or a program that´s has multiple “TYPE.SUBTYPE.filter” links
94 may use the second argument to identify the attachment´s mime type.
95 If the helper script is unable to process the attachment, at this
96 time, it should terminate with a non-zero exit code.
97 The default helper script for image attachments terminates with a
99 non-zero exit code if the DISPLAY environment variable is not
100 initialized. When invoked from an X-Windows terminal, image
101 attachments will be automatically displayed; and image attachments
102 are ignored otherwise on non-graphical consoles.
103 TYPE.SUBTYPE.filter filter type/subtype filename
105 If the helper script initially terminates with a zero exit code, it
107 will be invoked again after the MIME attachment is downloaded and
108 decoded. The first argument will be “filter”, and the attachment´s
109 filename is specified by the third argument.
110 Note
112 This is a temporary file, whose extension will not necessary be
113 the file extension associated with this MIME type.
114 The helper script should read and process the file specified by the
116 third argument. Cone interprets anything the helper script writes
117 to standard output as HTML.
118 Note
120 Cone waits until the helper script terminates before displaying
121 the rest of the message. Most helper scripts should run in the
122 background. However, note that Cone removes the temporary file
123 when the original message is closed; the temporary file may be
124 removed any time after the helper script terminates. The helper
125 script should make its own private copy of the file, if
126 necessary.
127 Activating URLs
129 Cone has limited ability to activate URLs in HTML messages. Cone
130 handles “mailto:” URLs by itself. For other URLs Cone runs
131 /usr/share/cone/method.handler with the URL passed as an argument.
132 Cone installs http.handler (hard linked to https.handler). This script
134 checks if firefox or mozilla binaries are found in the current PATH,
135 and runs them.
136 Note
138 Cone also looks method.handler in $HOME/.cone (or the directory
139 specified by -c) in addition to /usr/share/cone.
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142 $HOME/.cone
143 Configuration files, and other application data. May be modified by
144 the -c option.
145 /usr/share/cone/IMAGE.GIF.filter, /usr/share/cone/IMAGE.JPEG.filter,
147 /usr/share/cone/IMAGE.PNG.filter,
148 /usr/share/cone/APPLICATION.PDF.filter
149 Default helper scripts distributed with Cone.
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152 mailtool(1), sendmail(8).
153[FIXME: source] 05/08/2010 CONE(1)