| SEND(1mh) | SEND(1mh) |
send - send an nmh message
send [-help] [-version] [-alias aliasfile] [-draft] [-draftfolder +folder] [-draftmessage msg] [-nodraftfolder] [-filter filterfile] [-nofilter] [-format | -noformat] [-forward | -noforward] [-mime | -nomime] [-msgid | -nomsgid] [-messageid localname | random] [-push | -nopush] [-verbose | -noverbose] [-watch | -nowatch] [-mts smtp | sendmail/smtp | sendmail/pipe] [-sendmail program] [-server servername] [-port port-name/number] [-sasl] [-nosasl] [-saslmech mechanism] [-authservice service] [-snoop] [-user username] [-tls] [-initialtls] [-notls] [-certverify] [-nocertverify] [-width columns] [file ...]
send will cause each of the specified files to be delivered to each of the destinations in the “To:”, “cc:”, “Bcc:”, “Dcc:”, and “Fcc:” fields of the message. If send is re-distributing a message, as invoked from dist, then the corresponding “Resent-xxx” fields are examined instead.
By default, send uses the program post to do the actual delivery of the messages, although this can be changed by defining the postproc profile component. Most of the features attributed to send are actually performed by post.
Before send gives the message to post for delivery, the message is processed by mhbuild to perform any necessary MIME encoding of the outgoing message. This can be changed by the buildmimeproc profile component. mhbuild is invoked with the -auto switch, so mhbuild directives are not processed by default. See mhbuild(1) for more information.
mhbuild will scan the message draft for a header named Attach. The draft is converted to a MIME message if one or more matches are found. This conversion occurs before all other processing. whatnow(1) describes the user interface for managing MIME attachments via this mechanism.
The first part of the MIME message is the draft body if that body contains any non-blank characters. The body of each Attach header field is interpreted as a file name, and each file named is included as a separate part in the MIME message.
Determination of the content MIME type inserted into the Content-Type header for each part depends on how the nmh installation was configured. If a program, such as file with a --mime or -i option, was found that can specify the type of a file as a MIME type string, then that will be used. To determine if your nmh was so configured, run mhparam mimetypeproc and see if a non-empty string is displayed.
If your nmh was not configured with a program to specify a file type as a MIME string, then a different method is used to determine the content-type string. This method is also used if the configured mimetypeproc fails to find the MIME type of the content. For file names with dot suffixes, the profile is scanned for a mhshow-suffix- entry for that suffix. The content-type for the part is taken from that profile entry if a match is found. If a match is not found in the user profile, the mhn.defaults profile is scanned next. If no match is found or the file does not have a dot suffix, the content-type is text/plain if the file contains only ASCII characters or application/octet-stream if it contains characters outside of the ASCII range. See mhshow(1) for more details and example syntax.
Each attached MIME part contains a “Content-Description” header that includes the filename, and adds a “Content-Disposition” header. Here is an example of MIME part headers for an attachment:
Content-Type: text/plain; name="VERSION"; charset="us-ascii" Content-Description: VERSION Content-Disposition: attachment; filename="VERSION"
See mhbuild(1) for explanation of how the Content-Disposition value is selected.
If -push is specified, send will detach itself from the user's terminal and perform its actions in the background. If push'd and the draft can't be sent, then an error message will be sent (using the mailproc) back to the user. If -forward is given, then a copy of the draft will be attached to this failure notice. Using -push differs from putting send in the background because the output is trapped and analyzed by nmh.
If -verbose is specified, send will indicate the interactions occurring with the transport system, prior to actual delivery. If -watch is specified send will monitor the delivery of local and network mail. Hence, by specifying both switches, a large detail of information can be gathered about each step of the message's entry into the transport system.
The -draftfolder +folder and -draftmessage msg switches invoke the nmh draft folder facility. This is an advanced (and highly useful) feature. Consult mh-draft(5) for more information.
send with no file argument will query whether the draft is the intended file, whereas -draft will suppress this question. Once the transport system has successfully accepted custody of the message, the file will be renamed with a site-dependent prefix (usually a comma), which allows it to be retrieved until the next draft message is sent. If there are errors in the formatting of the message, send will abort with a (hopefully) helpful error message.
If a “Bcc:” field is encountered, its addresses will be used for delivery, and the “Bcc:” field will be removed from the message sent to sighted recipients. The blind recipients will receive an entirely new message with a minimal set of headers. The body of this new message will contain a copy of the message sent to the sighted recipients, either marked up with the indicator text "Blind-Carbon-Copy" or encapsulated as a MIME digest.
If a “Dcc:” field is encountered and the sendmail/pipe mail transport method is not in use, its addresses will be used for delivery, and the “Dcc:” field will be removed from the message. The blind recipients will receive exactly the same message as the sighted recipients. *WARNING* Recipients listed in the “Dcc:” field receive no explicit indication that they have received a “blind copy”. This can cause blind recipients to inadvertently reply to all of the sighted recipients of the original message, revealing that they received a blind copy. On the other hand, since a normal reply to a message sent via a “Bcc:” field will generate a reply only to the sender of the original message, it takes extra effort in most mailers to reply to the included message, and so would usually only be done deliberately, rather than by accident.
If the sendmail/pipe mail transport method is used, then messages containing a “Dcc:” field are rejected.
If -filter filterfile is specified, then this copy is filtered (re-formatted) by mhl prior to being sent to the blind recipients. Alternately, if you specify the -mime switch, then send will use the MIME rules for encapsulation.
Prior to sending the message, the “Date: now” field will be appended to the headers in the message. If -msgid is specified, then a “Message-ID:” field will also be added to the message.
The -messageid switch selects the style used for the part appearing after the @ in “Message-ID:”, “Resent-Message-ID:”, and “Content-ID:” header fields. The two acceptable options are localname (which is the default), and random. With localname, the local hostname is used. With random, a random sequence of characters is used instead. Note that the -msgid switch must be enabled for this switch to have any effect.
If send is re-distributing a message (when invoked by dist), then “Resent-” will be prepended to each of these fields: “From:”, “Date:”, and “Message-ID:”.
A “From:” field is required for all outgoing messages. Multiple addresses are permitted in the “From:” field, but a “Sender:” field is required in this case. Otherwise a “Sender:” field is optional.
If a message with multiple “From:” addresses does not include a “Sender:” field but does include an “Envelope-From:” field, the “Envelope-From:” field will be used to construct a “Sender:” field.
When using SMTP for mail submission, the envelope-from used for the SMTP transaction is derived from the “Envelope-From:” field. If no “Envelope-From:” field is present, the “Sender:” field is used. If neither the “Envelope-From:” nor the “Sender:” field is present, the “From:” field is used. When “Envelope-From:” appears in a message it will be removed from the final outgoing message.
By using the -format switch, each of the entries in the “To:” and “cc:” fields will be replaced with “standard” format entries. This standard format is designed to be usable by all of the message handlers on the various systems around the Internet. If -noformat is given, then headers are output exactly as they appear in the message draft.
If an “Fcc: folder” is encountered, the message will be copied to the specified folder for the sender in the format in which it will appear to any non-Bcc receivers of the message. That is, it will have the appended fields and field reformatting. The “Fcc:” fields will be removed from all outgoing copies of the message.
Beware that if an “Fcc:” with one or more folders is present but none of the folders exist, and the default fileproc and postproc are in use, then refile will prompt the user to create the folder(s) if -push is not specified. If all responses are negative, or creation of each folder fails, or -push is specified, the message will not be copied to any folder and will be removed by post. With the default refile switches, the message draft will be renamed according to the specification of its -nolink switch.
By using the -width columns switch, the user can direct send as to how long it should make header lines containing addresses.
The mail transport system default is provided in /etc/nmh/mts.conf but can be overridden here with the -mts switch.
If nmh is using sendmail/pipe or sendmail/smtp as its mail transport system, the -sendmail switch can be used to override the default sendmail program.
If nmh is using the SMTP MTA, the -server and the -port switches can be used to override the default mail server (defined by the /etc/nmh/mts.conf servers entry). The -snoop switch can be used to view the SMTP transaction. (Beware that the SMTP transaction may contain authentication information either in plaintext or easily decoded base64.) If -sasl -saslmech xoauth2 is used, the HTTP transaction is also shown.
If nmh has been compiled with SASL support, the -sasl and -nosasl switches will enable and disable the use of SASL authentication with the SMTP MTA. Depending on the SASL mechanism used, this may require an additional password prompt from the user (but the netrc file can be used to store this password, as described in mh-profile(5). The -saslmech switch can be used to select a particular SASL mechanism, and the -user switch can be used to select a authorization userid to provide to SASL other than the default. The credentials profile entry in mh-profile(5) describes the ways to supply a username and password.
If SASL authentication is successful, nmh will attempt to negotiate a security layer for session encryption. Encrypted data is labelled with `(encrypted)' and `(decrypted)' when viewing the SMTP transaction with the -snoop switch; see post(8)'s description of -snoop for its other features.
If nmh has been compiled with OAuth support, the -sasl and -saslmech xoauth2 switches will enable OAuth authentication. The -user switch must be used, and the username must be an email address the user has for the service, which must be specified with the -authservice service switch. Before using OAuth authentication, the user must authorize nmh by running mhlogin and grant authorization to that account. See mhlogin(1) for more details.
If nmh has been compiled with TLS support, the -tls and -initialtls switches will require the negotiation of TLS when connecting to the SMTP MTA. The -tls switch will negotiate TLS as part of the normal SMTP protocol using the STARTTLS command. The -initialtls will negotiate TLS immediately after the connection has taken place, before any SMTP commands are sent or received. Encrypted data is labelled with `(tls-encrypted)' and `(tls-decrypted)' when viewing the SMTP transaction with the -snoop switch; see post(8)'s description of -snoop for its other features. The -notls switch will disable all attempts to negotiate TLS.
If port 465 is specified and none of the TLS switches were enabled, -initialtls will be implied if TLS support was compiled in. Though port 465 for SMTPS (SMTP over SSL) was deregistered by IANA in 1998, it is still used for that service.
When using TLS the default is to verify the remote certificate and SubjectName against the local trusted certificate store. This can be controlled by the -certverify and -nocertverify switches. See your OpenSSL documentation for more information on certificate verification.
The files specified by the profile entry “Aliasfile:” and any additional alias files given by the -alias aliasfile switch will be read (more than one file, each preceded by -alias, can be named). See mh-alias(5) for more information.
One or more sendfrom profile components can be used to select a mail server address, mail server port, or any other switch that can be supplied to post. It works by first looking at the sender address and domain name in the message draft, as described below. It then looks for a corresponding profile entry, which contains the post switches. To enable, add profile entries of the form:
The email address is extracted from the Envelope-From: header, if not blank, the Sender: header, or the From: header line in the message draft. Multiple profile entries, with different email addresses or domain names, are supported. This allows different switches to post, such as -user, to be associated with different email addresses. If a domain name is used, it matches all users in that domain.
Here is an example profile entry to use the SMTP on the localhost when the sender address is clearly local:
sendfrom-localuser@localhost: -server localhost -port smtp
(Indentation indicates a continued line, as supported in MH profiles.) The username need not be the same as the sender address, which was extracted from the appropriate header line as noted above.
Here are example profile entries that use an nmh credentials file:
credentials: file:nmhcreds sendfrom-sendgrid_address@example.com: -sasl -tls
-server smtp.sendgrid.net
sendfrom-outbound.att.net: -sasl -initialtls
-server outbound.att.net -port 465
sendfrom-fastmail.com: -initialtls -sasl -saslmech LOGIN
-server smtps-proxy.messagingengine.com -port 80
where nmhcreds is in the user's nmh directory (from the Path profile component) and contains:
machine smtp.sendgrid.net
login sendgrid_login@example.com password ********
machine outbound.att.net
login att_login@example.com password ********
machine smtps-proxy.messagingengine.com
login fastmail_login@example.com password ********
For more information on authentication to mail servers, see mhlogin(1) for OAuth services, and mh-profile(5) for login credentials.
^$HOME/.mh_profile~^The user profile
^Path:~^To determine the user's nmh directory ^Aliasfile:~^For a default alias file ^Signature:~^To determine the user's mail signature ^mailproc:~^Program to post failure notices ^postproc:~^Program to post the message ^sendfrom-address:~^Switches to post for sender address ^sendfrom-domain:~^Switches to post for sender domain name
comp(1), dist(1), file(1), forw(1), mhbuild(1), mhparam(1), mhlogin(1), refile(1), repl(1), whatnow(1), mh-alias(5), mh-profile(5), mh-tailor(5), post(8)
`file' defaults to <mh-dir>/draft `-alias' defaults to /etc/nmh/MailAliases `-nodraftfolder' `-nofilter' `-format' `-forward' `-nomime' `-nomsgid' `-messageid localname' `-nopush' `-noverbose' `-nowatch' `-width 72' `-certverify'
None
Under some configurations, it is not possible to monitor the mail delivery transaction; -watch is a no-op on those systems.
| 2022-12-22 | nmh-1.8-RC2 |