mhl(1)							      General Commands Manual							    mhl(1)

NAME

       mhl - produce formatted listings of MH messages (only available within the message handling system, mh)

SYNOPSIS

       mhl [options] [files...]

OPTIONS

       Tells  mhl  to  ring  the  terminal  bell at the end of each page. This is the default behavior. You can suppress this by using the -nobell
       option.

	      This option takes effect only if the profile entry moreproc is defined but empty, and if mhl is outputting to  a	terminal.  If  the
	      moreproc	entry is defined and non-empty, and mhl is outputting to a terminal, then mhl causes the moreproc to be placed between the
	      terminal and mhl, and the switches are ignored.  Tells mhl to clear the screen at the end of each page, or output a  formfeed  after
	      each message. You can suppress this by using the -noclear option. The default behavior is -noclear.

	      This  option  takes  effect  only if the profile entry moreproc is defined but empty, and if mhl is outputting to a terminal. If the
	      moreproc entry in the user's is defined and non-empty, and mhl is outputting to a terminal, then mhl causes the moreproc program	to
	      be placed between the terminal and mhl, and the options are ignored.

	      If  the  -clear option is used and the output of mhl is directed to a terminal, then mhl consults the $TERM and $TERMCAP environment
	      variables to determine your terminal type in order to find out how to clear the screen. If the -clear switch is used and the  output
	      of  mhl  is  not	directed to a terminal (if, for example, it is directed to a pipe or a file), then mhl sends a formfeed after each
	      message.	Sets the folder name. This is used by components in the mhl.format form file to output the message name. If you do not use
	      this  option,  mhl  consults the environmental variable $mhfolder.  Specifies the format file used. If this option is not given, mhl
	      searches in your Mail directory for a file called mhl.format; or, if this file does not exist,  it  uses	the  system  default  file
	      /usr/lib/mh/mhl.format.	Prints	a  list  of the valid options to this command.	Sets the screen length. This defaults to the value
	      indicated by $TERMINFO, if appropriate; otherwise, it defaults to 40.  Sets the screen width. This defaults to the  value  indicated
	      by  $TERMINFO,  if appropriate; otherwise, it defaults to 80.  Overrides the default moreproc program.  Note that mhl never starts a
	      moreproc if invoked on a hardcopy terminal.

       The defaults for this command are:

       -bell -noclear -length 40 -width 80

DESCRIPTION

       The mhl command is a program for listing formatted messages, which can be used as a replacement for more, the default showproc program.

       As with more, each of the messages specified as arguments (or the standard input) are output. If more than one message file  is	specified,
       you are prompted prior to each one, and a <RETURN> or <EOT> begins the output. <RETURN> clears the screen (if appropriate), and <EOT>, usu-
       ally <CTRL/D>, suppresses the screen clear. An <INTERRUPT>, usually <CTRL/C>, aborts the current message output,  prompting  for  the  next
       message, if there is one.  A <QUIT>, usually <CTRL/E>, terminates the program without generating a core dump.

       The mhl command operates in two phases: it reads and parses the format file; then it processes each message (file). During the first phase,
       an internal description of the format is produced as a structured list. In the second phase, this list is traversed for each  message,  and
       message information is output according to the instructions contained in the format file.

   The Form File mhl.format
       The  mhl.format	form  file contains information controlling screen clearing, screen size, wrap-around control, transparent text, component
       ordering, and component formatting. A list of components that should be ignored may also be specified,  and  some  special  components  are
       defined to provide added functionality. Message output is in the order specified by the order in the format file.

       Each line of the mhl.format file has one of the following formats:

       ;comment :cleartext variable[variable...]  component:[variable...]

       A  line	beginning  with  a  semi  colon  (;) is a comment, and is ignored.  A line beginning with a colon (:) is clear text, and is output
       exactly as it is. A line containing only a colon (:) produces a blank line in the output.  A line beginning  with  component:  defines  the
       format  for  the  specified  component. Remaining lines define the global environment. Examples of these are given below, together with the
       system default form file.

       If variables or arguments follow a component, they apply only to that component; otherwise, their effect is global. Since the whole  format
       is parsed before any output processing, the last global switch setting for a variable applies to the whole message, provided that the vari-
       able is used in a global context (bell, clearscreen, width, length). All of the current variables and their arguments are shown in the fol-
       lowing table:

       ----------------------------------------------------------------
       Variable 	Type	   Semantics
       ----------------------------------------------------------------
       width		integer    screen width or component width
       length		integer    screen length or component length
       offset		integer    positions to indent the component
       overflowtext	string	   text to use at the beginning of an
				   overflow line
       overflowoffset	integer    positions to indent overflow lines
       compwidth	integer    positions  to indent component text
				   after the first line is output
       uppercase	option	   output text of  this  component  in
				   all
				   upper case
       nouppercase	option	   do not use uppercase
       clearscreen	option/G   clear the screen prior to each page
       noclearscreen	option/G   do not clear the screen
       bell		option/G   ring  the  bell  at the end of each
				   page
       nobell		option/G   disable bell
       component	string/L   name to use	instead  of  component
				   for this component
       nocomponent	option	   do  not  output component: for this
				   component
       center		option	   center component on line (works for
				   one-line components only)
       nocenter 	option	   do not center
       leftadjust	option	   strip  off  leading	white-space on
				   each line of text
       noleftadjust	option	   do not leftadjust
       compress 	option	   change newlines in text to spaces
       nocompress	option	   do not compress
       formatfield	string	   format string for this component
       addrfield	option	   field contains addresses
       datefield	option	   field contains dates
       ----------------------------------------------------------------

       To specify the value of integer-valued and string-valued variables, follow their name with an equals-sign (=) and the value. Integer-valued
       variables  are  given decimal values, while string-valued variables are given arbitrary text bracketed by double-quotes. If a value is suf-
       fixed by /G or /L, then its value is useful in a global-only or local-only context (respectively). A line of the form:

       ignores=component,...

       specifies a list of components which are never output.

       The component MessageName outputs the actual message name (file name) preceded by the folder name if one is specified or found in the envi-
       ronment. The format is identical to that produced by the -header option to show.

       The  component Extras outputs all of the components of the message which were not matched by explicit components, or included in the ignore
       list. If this component is not specified, an ignore list is not needed since all non-specified components are ignored.

       If -nocomponent is not specified, then the component name is output as it appears in the format file.

       The variable formatfield specifies a format string; see mh-format(4).  The variables addrfield and datefield, which are mutually exclusive,
       control the interpretation of the escapes.

       By default, mhl does not apply any formatting string to fields containing address or dates; see mh-mail(4) for a list of these fields. This
       results in faster operation since mhl must parse both addresses and dates in order to apply a format string to them.  If desired,  mhl  can
       be  given a default format string for either address or date fields, but not both. To do this, on a global line specify either the variable
       addrfield or the variable datefield, along with the variable formatfield.

PROFILE COMPONENTS

       Path: To determine your Mail directory

       moreproc: Program to use as interactive front-end

EXAMPLES

       The first example gives a typical line of a form file:

       width=80,length=40,clearscreen,overflowtext="***",overflowoffset=5

       The first two elements define the screen width to be 80 characters, and the screen length to be 40 lines. The  next  element,  clearscreen,
       specifies  that	the screen should be cleared prior to each page.  The next element, overflowoffset=5, states that the overflow indentation
       is 5. The final element, overflowtext="***", specifies that overflow text should be optionged with three asterisks.

       The system default form file, /usr/lib/mh/mhl.format, is:

       : -- using  template  mhl.format  -  -  overflowtext="***",overflowoffset=5  leftadjust,compwidth=9  ignores=msid,msgid,message-id,received
       Date:formatfield="%<(nodate{text})%{text}%|%(pretty{text})%>"  To:  cc:	: From: Subject: : extras:nocomponent : body:nocomponent,overflow-
       text=,overflowoffset=0,noleftadjust

FILES

       The system default form file, used to format message.  The user-supplied alternate to the system default form file.  The user profile.

SEE ALSO

       more(1), show(1), mh_profile(4), ap(8), dp(8)

																	    mhl(1)