MAN page from RedHat Other mh-6.8.3-15.i386.rpm

MHL

Section: User Commands (1)
Updated: MH.6.8
Index

NAME

mhl - produce formatted listings of MH messages

SYNOPSIS

/usr/lib/mh/mhl[-bell] [-nobell][-clear] [-noclear][-folder +folder][-form formfile][-length lines] [-width columns] [-moreproc program] [-nomoreproc][files ...][-help]

DESCRIPTION

Mhl is a formatted message listing program.It can be used as a replacement for more (1)(the default showproc ).As with more,each of the messages specified as arguments (or the standard input) will beoutput.If more than one message file is specified,the user will be prompted prior to each one,and a <RETURN> or <EOT> will begin the output,with <RETURN> clearing the screen (if appropriate),and <EOT> (usually CTRL-D) suppressing the screen clear.An <INTERRUPT> (usually CTRL-C) will abort the current message output,prompting for the next message (if there is one),and a <QUIT> (usually CTRL-\) will terminate the program (without core dump).

The `-bell' option tells mhl to ring the terminal's bell at the end of each page,while the `-clear' option tells mhl to clear the scree at the end ofeach page (or output a formfeed after each message).Both of these switches (and their inverse counterparts)take effect only if the profile entry moreproc is defined but empty,and mhl is outputting to a terminal.If the moreproc entry is defined and non-empty,and mhl is outputting to a terminal,then mhl will cause the moreproc to be placed between theterminal and mhl and the switches are ignored.Furthermore,if the `-clear' switch is used and mhl's output is directed to aterminal,then mhl will consult the $TERM and $TERMCAPenvariables to determine the user'sterminal type in order to find out how to clear the screen.If the `-clear' switch is used and mhl's output is not directed toa terminal (e.g., a pipe or a file),then mhl will send a formfeed after each message.

To override the default moreproc and the profile entry,use the `-moreproc program' switch.Note that mhl will never start a moreproc if invoked on ahardcopy terminal.

The `-length length' and `-width width' switches set the screen length andwidth, respectively.These default to the values indicated by $TERMCAP,if appropriate,otherwise they default to 40 and 80, respectively.

The default format file used by mhl is called mhl.format(which is first searched for in the user's MH directory,and then sought in the /usr/lib/mh directory),this can be changed by using the `-form formatfile' switch.

Finally,the `-folder +folder' switch sets the MH folder name,which is used for the ``messagename:'' field described below.The envariable $mhfolder is consulted for the default value,which show, next, and prev initialize appropriately.

Mhl operates in two phases:1) read and parse the format file,and 2) process each message (file).During phase 1,an internal description of the format is produced as a structured list.In phase 2,this list is walked for each message,outputting message information under the format constraints from the formatfile.

The ``mhl.format'' form file contains information controllingscreen clearing, screen size, wrap-around control, transparent text,component ordering, and component formatting.Also, a list of components to ignore may be specified,and a couple of ``special'' components are defined to provide addedfunctionality.Message output will be in the order specified by the order in the format file.

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

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

A line beginning with a `;' is a comment, and is ignored.A line beginning with a `:' is clear text,and is output exactly as is.A line containing only a `:' produces a blank line in the output.A line beginning with ``component:'' defines the format for the specifiedcomponent,and finally, remaining lines define the global environment.

For example, the line:

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

defines the screen size to be 80 columns by 40 rows,specifies that the screen should be cleared prior to each page,that the overflow indentation is 5,and that overflow text should be flagged with ``***''.

Following are all of the current variables and their arguments.If they follow a component,they apply only to that component,otherwise, their affect is global.Since the whole format is parsed before any output processing,the last global switch setting for a variable applies to the whole messageif that variable is used in a global context(i.e., bell, clearscreen, width, length).

variable       type       semanticswidth          integer    screen width or component widthlength         integer    screen length or component lengthoffset         integer    positions to indent ``component: ''overflowtext   string     text to use at the beginning of an                          overflow lineoverflowoffset integer    positions to indent overflow linescompwidth      integer    positions to indent component text                          after the first line is outputuppercase      flag       output text of this component in all                          upper casenouppercase    flag       don't uppercaseclearscreen    flag/G     clear the screen prior to each pagenoclearscreen  flag/G     don't clearscreenbell           flag/G     ring the bell at the end of each pagenobell         flag/G     don't bellcomponent      string/L   name to use instead of ``component'' for                          this componentnocomponent    flag       don't output ``component: '' for this                          componentcenter         flag       center component on line (works for                          one-line components only)nocenter       flag       don't centerleftadjust     flag       strip off leading whitespace on each                          line of textnoleftadjust   flag       don't leftadjustcompress       flag       change newlines in text to spacesnocompress     flag       don't compresssplit          flag       don't combine multiple fields into a single fieldnosplit        flag       combine multiple fields into a single fieldnewline        flag       print newline at end of components (default)nonewline      flag       don't print newline at end of componentsformatfield    string     format string for this component (see below)addrfield      flag       field contains addressesdatefield      flag       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 bydouble-quotes.If a value is suffixed 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'' (case-insensitive)will output the actual message name (file name) preceded bythe folder name if one is specified or found in the environment.The format is identical to that produced by the `-header' option toshow.

The component ``Extras'' will output all of the components of the messagewhich 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 will beignored.

If ``nocomponent'' is NOT specified, then the component name will beoutput as it appears in the format file.

The default format is:

man2html: unable to open or read file/usr/lib/mh/mhl.format

The variable ``formatfield'' specifies a format string(see mh-format (5)).The flag variables ``addrfield'' and ``datefield''(which are mutually exclusive),tell mhl to interpret the escapes in the format stringas either addresses or dates, respectively.

By default,mhl does not apply any formatting string to fields containing address ordates (see mh-mail (5) for a list of these fields).Note that this results in faster operationsince mhl must parse both addresses and dates in order to apply aformat string to them.If desired,mhl can be given a default format string for either address or datefields (but not both).To do this,on a global line specify: either the flag addrfield or datefield,along with the apropriate formatfield variable string.^/usr/lib/mh/mhl.format~^The message template^or <mh-dir>/mhl.format~^Rather than the standard template^$HOME/.mh_profile~^The user profile^moreproc:~^Program to use as interactive front-endshow(1), ap(8), dp(8)`-bell'`-noclear'`-length 40'`-width 80'NoneThere should be some way to pass `bell' and `clear' information to the front-end.

On hosts where MH was configured with the BERK option,address parsing is not enabled.

The ``nonewline'' option interacts badly with ``compress'' and ``split''.

This document was created byman2html,using the manual pages.