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.\"	@(#)mail.1	8.8 (Berkeley) 4/28/95
.\"
.Dd April 28, 1995
.Dt MAIL 1
.Os
.Sh NAME
.Nm mail ,
.Nm mailx ,
.Nm Mail
.Nd send and receive mail
.Sh SYNOPSIS
.Nm mail
.Op Fl iInv
.Op Fl s Ar subject
.Op Fl c Ar list
.Op Fl b Ar list
.Ar to-addr Op Ar ...
.Op Fl Ar sendmail-options Op Ar ...
.Nm mail
.Op Fl iInNv
.Fl f
.Op Ar name
.Nm mail
.Op Fl iInNv
.Op Fl u Ar user
.Sh DESCRIPTION
.Nm mail
is an intelligent mail processing system which has
a command syntax reminiscent of
.Xr \&ed 1
with lines replaced by messages.
.Pp
The options are as follows:
.Bl -tag -width flag
.It Fl v
Verbose mode.
The details of
delivery are displayed on the user's terminal.
.It Fl i
Ignore tty interrupt signals.
This is
particularly useful when using
.Nm mail
on noisy phone lines.
.It Fl I
Forces
.Nm mail
to run in interactive mode, even when input is not a terminal.
In particular, the special
.Ic \&~
command character, used when sending mail, is only available interactively.
.It Fl n
Inhibits reading
.Pa /etc/mail.rc
upon startup.
.It Fl N
Inhibits initial display of message headers
when reading mail or editing a mail folder.
.It Fl s Ar subject
Specify subject on command line
(only the first argument after the
.Fl s
flag is used as a subject; be careful to quote subjects
containing spaces).
.It Fl c Ar list
Send carbon copies to
.Ar list
of users.
.Ar list
should be a comma separated list of names.
.It Fl b Ar list
Send blind carbon copies to
.Ar list .
.It Fl f Ar name
Read in the contents of your mailbox
(or the specified file
.Ar name )
for processing; when you quit,
.Nm mail
writes undeleted messages back to this file.
.It Fl u Ar user
Is equivalent to:
.Pp
.Dl mail -f /var/mail/user
.Pp
except that locking is done.
.El
.Ss Startup actions
At startup time,
.Nm mail
will execute commands in the system command files
.Pa /usr/share/misc/mail.rc ,
.Pa /usr/local/etc/mail.rc
and
.Pa /etc/mail.rc
in order unless explicitly told not to by using the
.Fl n
option.
Next, the commands in the user's personal command file
.Pa ~/.mailrc
are executed.
.Nm mail
then examines its command line options to determine whether the user
requested a new message to be sent or existing messages in a mailbox
to be examined.
.Ss Sending mail
To send a message to one or more people,
.Nm mail
can be invoked with arguments which are the names of people to
whom the mail will be sent.
You are then expected to type in
your message, followed
by a control-D
.Pq Sq ^D
at the beginning of a line.
The section below,
.Ar Replying to or originating mail ,
describes some features of
.Nm mail
available to help you compose your letter.
.Pp
.Ss Reading mail
In normal usage,
.Nm mail
is given no arguments and checks your mail out of the
post office, then
prints out a one line header of each message found.
The current message is initially set to the first message (numbered 1)
and can be printed using the
.Ic print
command (which can be abbreviated
.Ic p ) .
Moving among the messages is much like moving between lines in
.Xr ed 1 ;
you may use
.Ic \&+
and
.Ic \&-
to shift forwards and backwards, or simply enter a message number to move
directly.
.Pp
.Ss Disposing of mail
After examining a message you can
.Ic delete
.Pq Ic d
or
.Ic reply
.Pq Ic r
to it.
Deletion causes the
.Nm mail
program to forget about the message.
This is not irreversible; the message can be
.Ic undeleted
.Pq Ic u
by giving its number, or the
.Nm mail
session can be aborted by giving the
.Ic exit
.Pq Ic x
command.
Deleted messages, however, will usually disappear, never to be seen again.
.Pp
.Ss Specifying messages
Commands such as
.Ic print
and
.Ic delete
can be given a list of message numbers as arguments to apply
to a number of messages at once.
Thus
.Ic delete 1 2
deletes messages 1 and 2, while
.Ic delete 1\-5
deletes messages 1 through 5.
The special name
.Sq \&*
addresses all messages and
.Sq \&$
addresses
the last message; thus the command
.Ic top
which prints the first few lines of a message could be used in
.Ic top \&*
to print the first few lines of all messages.
.Pp
.Ss Replying to or originating mail
You can use the
.Ic reply
command to
set up a response to a message, sending it back to the
person who it was from.
Text you then type in, up to an end-of-file,
defines the contents of the message.
While you are composing a message,
.Nm mail
treats lines beginning with the tilde
.Pq Sq ~
character specially.
For instance, typing
.Ic ~m
(alone on a line) will place a copy
of the current message into the response, right shifting it by a single
tab-stop (see
.Va indentprefix
variable, below).
Other escapes will set up subject fields, add and delete recipients
to the message and allow you to escape to an editor to revise the
message or to a shell to run some commands.
(These options
are given in the summary below.)
.Pp
.Ss Ending a mail processing session
You can end a
.Nm mail
session with the
.Ic quit
.Pq Ic q
command.
Messages which have been examined go to your
.Ar mbox
file unless they have been deleted in which case they are discarded.
Unexamined messages go back to the post office (see the
.Fl f
option above).
.Pp
.Ss Personal and system wide distribution lists
It is also possible to create personal distribution lists so that,
for instance, you can send mail to
.Dq Li cohorts
and have it go
to a group of people.
Such lists can be defined by placing a line like
.Pp
.Dl alias cohorts bill ozalp jkf mark kridle@ucbcory
.Pp
in the file
.Pa \&.mailrc
in your home directory.
The current list of such aliases can be displayed with the
.Ic alias
command in
.Nm mail .
System wide distribution lists can be created by editing
.Pa /etc/mail/aliases ,
(see
.Xr aliases 5
and
.Xr sendmail 8 ) ;
these are kept in a different syntax.
In mail you send, personal aliases will be expanded in mail sent
to others so that they will be able to
.Ic reply
to the recipients.
System wide aliases
are not expanded when the mail is sent,
but any reply returned to the machine will have the system wide
alias expanded as all mail goes through
.Xr sendmail .
.Pp
.Ss Network mail (ARPA, UUCP, Berknet)
See
.Xr mailaddr 7
for a description of network addresses.
.Pp
.Nm mail
has a number of options which can be set in the
.Pa .mailrc
file to alter its behavior; thus
.Ic set askcc
enables the
.Ar askcc
feature.
(These options are summarized below.)
.Sh SUMMARY
(Adapted from the
.Dq Mail Reference Manual . )
.Pp
Each command is typed on a line by itself, and may take arguments
following the command word.
The command need not be typed in its
entirety -- the first command which matches the typed prefix is used.
For commands which take message lists as arguments, if no message
list is given, then the next message forward which satisfies the
command's requirements is used.
If there are no messages forward of
the current message, the search proceeds backwards, and if there are no
good messages at all,
.Nm mail
types
.Dq Li \&No applicable messages
and
aborts the command.
.Bl -tag -width delete
.It Ic \&\-
Print out the preceding message.
If given a numeric
argument
.Ar n ,
goes to the
.Ar n Ns th
previous message and prints it.
.It Ic \&?
Prints a brief summary of commands.
.It Ic \&!
Executes the shell
(see
.Xr sh 1
and
.Xr csh 1 )
command which follows.
.It Ic Print
.Pq Ic P
Like
.Ic print
but also prints out ignored header fields.
See also
.Ic print ,
.Ic ignore
and
.Ic retain .
.It Ic Reply
.Pq Ic R
Reply to originator.
Does not reply to other
recipients of the original message.
.It Ic Type
.Pq Ic T
Identical to the
.Ic Print
command.
.It Ic alias
.Pq Ic a
With no arguments, prints out all currently defined aliases.
With one
argument, prints out that alias.
With more than one argument, creates
a new alias or changes an old one.
.It Ic alternates
.Pq Ic alt
The
.Ic alternates
command is useful if you have accounts on several machines.
It can be used to inform
.Nm mail
that the listed addresses are really you.
When you
.Ic reply
to messages,
.Nm mail
will not send a copy of the message to any of the addresses
listed on the
.Ic alternates
list.
If the
.Ic alternates
command is given with no argument, the current set of alternate
names is displayed.
.It Ic chdir
.Pq Ic c
Changes the user's working directory to that specified, if given.
If
no directory is given, then changes to the user's login directory.
.It Ic copy
.Pq Ic co
The
.Ic copy
command does the same thing that
.Ic save
does, except that it does not mark the messages it
is used on for deletion when you quit.
.It Ic delete
.Pq Ic d
Takes a list of messages as argument and marks them all as deleted.
Deleted messages will not be saved in
.Ar mbox ,
nor will they be available for most other commands.
.It Ic dp
(also
.Ic dt )
Deletes the current message and prints the next message.
If there is no next message,
.Nm mail
says
.Dq Li "at EOF" .
.It Ic edit
.Pq Ic e
Takes a list of messages and points the text editor at each one in
turn.
On return from the editor, the message is read back in.
.It Ic exit
.Pf ( Ic ex
or
.Ic x )
Effects an immediate return to the shell without
modifying the user's system mailbox, his
.Ar mbox
file, or his edit file in
.Fl f .
.It Ic file
.Pq Ic fi
The same as
.Ic folder .
.It Ic folders
List the names of the folders in your folder directory.
.It Ic folder
.Pq Ic fo
The
.Ic folder
command switches to a new mail file or folder.
With no
arguments, it tells you which file you are currently reading.
If you give it an argument, it will write out changes (such
as deletions) you have made in the current file and read in
the new file.
Some special conventions are recognized for
the name.
# means the previous file, % means your system
mailbox, %user means user's system mailbox, & means
your
.Ar mbox
file, and
\&+\&folder means a file in your folder
directory.
.It Ic from
.Pq Ic f
Takes a list of messages and prints their message headers.
.It Ic headers
.Pq Ic h
Lists the current range of headers, which is an 18\-message group.
If
a
.Ql \&+
argument is given, the next 18\-message group is printed; if
a
.Ql \&\-
argument is given, the previous 18\-message group is printed.
.It Ic help
A synonym for
.Ic \&? .
.ne li
.It Ic hold
.Pf ( Ic ho ,
also
.Ic preserve )
Takes a message list and marks each
message therein to be saved in the
user's system mailbox instead of in
.Ar mbox .
Does not override the
.Ic delete
command.
.It Ic ignore
Add the list of header fields named to the
.Ar ignored list .
Header fields in the ignore list are not printed
on your terminal when you print a message.
This
command is very handy for suppression of certain machine-generated
header fields.
The
.Ic Type
and
.Ic Print
commands can be used to print a message in its entirety, including
ignored fields.
If
.Ic ignore
is executed with no arguments, it lists the current set of
ignored fields.
.It Ic inc
Incorporate any new messages that have arrived while mail
is being read.
The new messages are added to the end of the message list,
and the current message is reset to be the first new mail message.
This does not renumber the existing message list, nor
does it cause any changes made so far to be saved.
.It Ic mail
.Pq Ic m
Takes as argument login names and distribution group names and sends
mail to those people.
.It Ic mbox
Indicate that a list of messages be sent to
.Ic mbox
in your home directory when you quit.
This is the default
action for messages if you do
.Em not
have the
.Ic hold
option set.
.It Ic more
.Pq Ic \mo
Takes a message list and invokes the pager on that list.
.It Ic next
.Pq Ic n
(like
.Ic \&+
or
.Tn CR )
Goes to the next message in sequence and types it.
With an argument list, types the next matching message.
.It Ic preserve
.Pq Ic pre
A synonym for
.Ic hold .
.It Ic print
.Pq Ic p
Takes a message list and types out each message on the user's terminal.
.It Ic quit
.Pq Ic q
Terminates the session, saving all undeleted, unsaved messages in
the user's
.Ar mbox
file in his login directory, preserving all messages marked with
.Ic hold
or
.Ic preserve
or never referenced
in his system mailbox, and removing all other messages from his system
mailbox.
If new mail has arrived during the session, the message
.Dq Li "You have new mail"
is given.
If given while editing a
mailbox file with the
.Fl f
flag, then the edit file is rewritten.
A return to the shell is
effected, unless the rewrite of edit file fails, in which case the user
can escape with the
.Ic exit
command.
.It Ic reply
.Pq Ic r
Takes a message list and sends mail to the sender and all
recipients of the specified message.
The default message must not be deleted.
.It Ic respond
A synonym for
.Ic reply .
.It Ic retain
Add the list of header fields named to the
.Ar retained list .
Only the header fields in the retain list
are shown on your terminal when you print a message.
All other header fields are suppressed.
The
.Ic Type
and
.Ic Print
commands can be used to print a message in its entirety.
If
.Ic retain
is executed with no arguments, it lists the current set of
retained fields.
.It Ic save
.Pq Ic s
Takes a message list and a filename and appends each message in
turn to the end of the file.
The filename in quotes, followed by the line
count and character count is echoed on the user's terminal.
.It Ic set
.Pq Ic se
With no arguments, prints all variable values.
Otherwise, sets
option.
Arguments are of the form
.Ar option=value
(no space before or after =) or
.Ar option .
Quotation marks may be placed around any part of the assignment statement to
quote blanks or tabs, i.e.,
.Ic set indentprefix="->" .
.It Ic saveignore
.Ic saveignore
is to
.Ic save
what
.Ic ignore
is to
.Ic print
and
.Ic type .
Header fields thus marked are filtered out when
saving a message by
.Ic save
or when automatically saving to
.Ar mbox .
.pl +1
.It Ic saveretain
.Ic saveretain
is to
.Ic save
what
.Ic retain
is to
.Ic print
and
.Ic type .
Header fields thus marked are the only ones saved
with a message when saving by
.Ic save
or when automatically saving to
.Ar mbox .
.Ic saveretain
overrides
.Ic saveignore .
.It Ic shell
.Pq Ic sh
Invokes an interactive version of the shell.
.It Ic size
Takes a message list and prints out the size in characters of each
message.
.It Ic source
The
.Ic source
command reads
commands from a file.
.It Ic top
Takes a message list and prints the top few lines of each.
The number of
lines printed is controlled by the variable
.Ic toplines
and defaults to five.
.It Ic type
.Pq Ic t
A synonym for
.Ic print .
.It Ic unalias
Takes a list of names defined by
.Ic alias
commands and discards the remembered groups of users.
The group names
no longer have any significance.
.It Ic undelete
.Pq Ic u
Takes a message list and marks each message as
.Ic not
being deleted.
.It Ic unread
.Pq Ic U
Takes a message list and marks each message as
.Ic not
having been read.
.It Ic unset
Takes a list of option names and discards their remembered values;
the inverse of
.Ic set .
.It Ic visual
.Pq Ic v
Takes a message list and invokes the display editor on each message.
.It Ic write
.Pq Ic w
Similar to
.Ic save ,
except that
.Ic only
the message body
.Pf ( Ar without
the header)
is saved.
Extremely useful for such tasks as sending and receiving source
program text over the message system.
.It Ic xit
.Pq Ic x
A synonym for
.Ic exit .
.It Ic z
.Nm mail
presents message headers in windowfuls as described under the
.Ic headers
command.
You can move
.Nm mail Ns 's
attention forward to the next window with the
.Ic \&z
command.
Also, you can move to the previous window by using
.Ic \&z\&\- .
.El
.Ss Tilde/escapes
Here is a summary of the tilde escapes,
which are used when composing messages to perform
special functions.
Tilde escapes are only recognized at the beginning
of lines.
The name
.Dq tilde escape
is somewhat of a misnomer since the actual escape character can be set
by the option
.Ic escape .
.Bl -tag -width Ds
.It Ic \&~! Ns Ar command
Execute the indicated shell command, then return to the message.
.It Ic \&~b Ns Ar name ...
Add the given names to the list of carbon copy recipients but do not make
the names visible in the Cc: line ("blind" carbon copy).
.It Ic \&~c Ns Ar name ...
Add the given names to the list of carbon copy recipients.
.It Ic \&~d
Read the file
.Pa dead.letter
from your home directory into the message.
.It Ic \&~e
Invoke the text editor on the message collected so far.
After the
editing session is finished, you may continue appending text to the
message.
.It Ic \&~f Ns Ar messages
Read the named messages into the message being sent.
If no messages are specified, read in the current message.
Message headers currently being ignored (by the
.Ic ignore
or
.Ic retain
command) are not included.
.ne li
.It Ic \&~F Ns Ar messages
Identical to
.Ic \&~f ,
except all message headers are included.
.It Ic \&~h
Edit the message header fields by typing each one in turn and allowing
the user to append text to the end or modify the field by using the
current terminal erase and kill characters.
.It Ic \&~m Ns Ar messages
Read the named messages into the message being sent, indented by a
tab or by the value of
.Va indentprefix .
If no messages are specified,
read the current message.
Message headers currently being ignored (by the
.Ic ignore
or
.Ic retain
command) are not included.
.It Ic \&~M Ns Ar messages
Identical to
.Ic \&~m ,
except all message headers are included.
.It Ic \&~p
Print out the message collected so far, prefaced by the message header
fields.
.It Ic \&~q
Abort the message being sent, copying the message to
.Pa dead.letter
in your home directory if
.Ic save
is set.
.It Ic \&~r Ns Ar filename
Read the named file into the message.
.It Ic \&~s Ns Ar string
Cause the named string to become the current subject field.
.It Ic \&~\&t Ns Ar name ...
Add the given names to the direct recipient list.
.It Ic \&~\&v
Invoke an alternate editor (defined by the
.Ev VISUAL
option) on the
message collected so far.
Usually, the alternate editor will be a
screen editor.
After you quit the editor, you may resume appending
text to the end of your message.
.It Ic \&~w Ns Ar filename
Write the message onto the named file.
.It Ic \&~\&| Ns Ar command
Pipe the message through the command as a filter.
If the command gives
no output or terminates abnormally, retain the original text of the
message.
The command
.Xr fmt 1
is often used as
.Ic command
to rejustify the message.
.It Ic \&~: Ns Ar mail-command
Execute the given mail command.
Not all commands, however, are allowed.
.It Ic \&~~ Ns Ar string
Insert the string of text in the message prefaced by a single ~.
If
you have changed the escape character, then you should double
that character in order to send it.
.El
.Ss Mail options
Options are controlled via
.Ic set
and
.Ic unset
commands.
Options may be either binary, in which case it is only
significant to see whether they are set or not; or string, in which
case the actual value is of interest.
The binary options include the following:
.Bl -tag -width append
.It Ar append
Causes messages saved in
.Ar mbox
to be appended to the end rather than prepended.
This should always be set (perhaps in
.Pa /etc/mail.rc ) .
.It Ar ask , asksub
Causes
.Nm mail
to prompt you for the subject of each message you send.
If
you respond with simply a newline, no subject field will be sent.
.ne li
.It Ar askcc
Causes you to be prompted for additional carbon copy recipients at the
end of each message.
Responding with a newline indicates your
satisfaction with the current list.
.It Ar autoinc
Causes new mail to be automatically incorporated when it arrives.
Setting this is similar to issuing the
.Ic inc
command at each prompt, except that the current message is not
reset when new mail arrives.
.It Ar askbcc
Causes you to be prompted for additional blind carbon copy recipients at the
end of each message.
Responding with a newline indicates your
satisfaction with the current list.
.It Ar autoprint
Causes the
.Ic delete
command to behave like
.Ic dp ;
thus, after deleting a message, the next one will be typed
automatically.
.It Ar debug
Setting the binary option
.Ar debug
is the same as specifying
.Fl d
on the command line and causes
.Nm mail
to output all sorts of information useful for debugging
.Nm mail .
.It Ar dot
The binary option
.Ar dot
causes
.Nm mail
to interpret a period alone on a line as the terminator
of a message you are sending.
.It Ar hold
This option is used to hold messages in the system mailbox
by default.
.It Ar ignore
Causes interrupt signals from your terminal to be ignored and echoed as
@'s.
.It Ar ignoreeof
An option related to
.Ar dot
is
.Ar ignoreeof
which makes
.Nm mail
refuse to accept a control-d as the end of a message.
.Ar ignoreeof
also applies to
.Nm mail
command mode.
.It Ar metoo
Usually, when a group is expanded that contains the sender, the sender
is removed from the expansion.
Setting this option causes the sender
to be included in the group.
.It Ar noheader
Setting the option
.Ar noheader
is the same as giving the
.Fl N
flag on the command line.
.It Ar nosave
Normally, when you abort a message with two
.Tn RUBOUT
(erase or delete)
.Nm mail
copies the partial letter to the file
.Pa dead.letter
in your home directory.
Setting the binary option
.Ar nosave
prevents this.
.It Ar Replyall
Reverses the sense of
.Ic reply
and
.Ic Reply
commands.
.It Ar quiet
Suppresses the printing of the version when first invoked.
.It Ar searchheaders
If this option is set, then a message-list specifier in the form
.Dq /x:y
will expand to all messages containing the substring
.Dq y
in the header
field
.Dq x .
The string search is case insensitive.
If
.Dq x
is omitted, it will default to the
.Dq Subject
header field.
The form
.Dq /to:y
is a special case, and will expand
to all messages containing the substring
.Dq y
in the
.Dq To ,
.Dq Cc
or
.Dq Bcc
header fields.
The check for
.Dq to
is case sensitive, so that
.Dq /To:y
can be used to limit the search for
.Dq y
to just the
.Dq To:
field.
.It Ar verbose
Setting the option
.Ar verbose
is the same as using the
.Fl v
flag on the command line.
When mail runs in verbose mode,
the actual delivery of messages is displayed on the user's
terminal.
.El
.Ss Option string values
.Bl -tag -width Va
.It Ev EDITOR
Pathname of the text editor to use in the
.Ic edit
command and
.Ic \&~e
escape.
If not defined, then a default editor is used.
.It Ev LISTER
Pathname of the directory lister to use in the
.Ic folders
command.
Default is
.Pa /bin/ls .
.It Ev PAGER
Pathname of the program to use in the
.Ic more
command or when
.Ic crt
variable is set.
The default paginator
.Xr more 1
is used if this option is not defined.
.It Ev SHELL
Pathname of the shell to use in the
.Ic \&!
command and the
.Ic \&~!
escape.
A default shell is used if this option is
not defined.
.It Ev VISUAL
Pathname of the text editor to use in the
.Ic visual
command and
.Ic \&~v
escape.
.ne li
.It Va crt
The valued option
.Va crt
is used as a threshold to determine how long a message must
be before
.Ev PAGER
is used to read it.
If
.Va crt
is set without a value,
then the height of the terminal screen stored in the system
is used to compute the threshold (see
.Xr stty 1 ) .
.It Ar escape
If defined, the first character of this option gives the character to
use in the place of ~ to denote escapes.
.It Ar folder
The name of the directory to use for storing folders of
messages.
If this name begins with a
.Ql / ,
.Nm mail
considers it to be an absolute pathname; otherwise, the
folder directory is found relative to your home directory.
.It Ev MBOX
The name of the
.Ar mbox
file.
It can be the name of a folder.
The default is
.Dq Li mbox
in the user's home directory.
.It Ar record
If defined, gives the pathname of the file used to record all outgoing
mail.
If not defined, then outgoing mail is not so saved.
.It Ar indentprefix
String used by the
.Ic \&~m
tilde escape for indenting messages, in place of the normal tab character
.Pq Sq ^I
Be sure to quote the value if it contains
spaces or tabs.
.It Ar toplines
If defined, gives the number of lines of a message to be printed out
with the
.Ic top
command; normally, the first five lines are printed.
.El
.Sh ENVIRONMENT
.Nm mail
utilizes the
.Ev HOME ,
.Ev LOGNAME ,
and
.Ev USER
environment variables.
.Pp
If the
.Ev MAIL
environment variable is set, its value is used as the path to the
user's mail spool.
.Sh FILES
.Bl -tag -width /usr/share/misc/mail.*help -compact
.It Pa /var/mail/*
post office (unless overridden by the
.Ev MAIL
environment variable)
.It ~/mbox
user's old mail
.It ~/.mailrc
file giving initial mail commands; can be overridden by setting the
.Ev MAILRC
environment variable
.It Pa /tmp/R*
temporary files
.It Pa /usr/share/misc/mail.*help
help files
.It Pa /etc/mail.rc
system initialization file
.El
.Sh SEE ALSO
.Xr fmt 1 ,
.Xr lockspool 1 ,
.Xr vacation 1 ,
.Xr aliases 5 ,
.Xr mailaddr 7 ,
.Xr mail.local 8 ,
.Xr newaliases 8 ,
.Xr sendmail 8
.Rs
.%T "The Mail Reference Manual"
.Re
.Sh HISTORY
A
.Nm mail
command appeared in
.At v5 .
This man page is derived from
.%T "The Mail Reference Manual"
originally written by Kurt Shoens.
.Sh BUGS
There are some flags that are not documented here.
Most are
not useful to the general user.
.Pp
Usually,
.Nm mail
and
.Nm mailx
are just links to
.Nm Mail ,
which can be confusing.