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signify

NAME

signify - Program to generate semi-random signatures

SYNOPSIS

signify [--fifo=$HOME/.signature] [--input=file] [--debug]

DESCRIPTION

Signify will take a signature description file ( ~/.signify or whatever file is specified by the --input=<file> option ) and create a random signature based on the information contained therein. This allows the ability to do such things as pick a random quote for each message sent.

Signify, by default, will write the generated signature to standard output from where it can be redirected to overwrite the .signature file. Alternatively, Signify can pipe it's output to a given 'fifo'. Each read from that file will return a different signature.

To use the FIFO feature, delete the current "$HOME/.signature" file and start Signify in the background like "signify --fifo=$HOME/.signature &". With this running, try "cat $HOME/.signature" a few times. A different signature will be returned each time. (Note: This feature will probably work only on unix systems.)

The --debug switch causes Signify to generate messages on what it is doing to stderr. This switch is only meant to be useful to the program's maintainers.

CONFIGURATION

The definition for the generated signatures is contained entirely within the .signify file contained in the user's home directory. Any completely empty lines (lines with even a single space are considered part of the signature data) and those lines starting with a hash character (#) are completely ignored. Those lines starting with a percent sign (%) are considered commands and affect the way Signify behaves.

Perl Command Substitution

Signify can execute an arbitrary perl code fragment during the initial reading of the configuration file. This can be used, for example, to choose values or text depending on the environment in which Signify is being run. To use this feature, simply enclose the desired perl code in back-tics (i.e. `perl code`). Whatever the perl code evaluates to will be substituted in that spot. No further variable substitutions are made on the resulting text. Signify is intelligent enough to recognize two back-tics together (often used as a better looking quotation mark) as not being a code fragment. Thus, writting something like "``Stop,'' she said." will appear as expected. Note: The entire code fragment must be contained on a single line of the input file.

Defining Variables

Signify will substitute variables within each line of the signature in much the same way as the shell would. Any sequence of $WORD; will be replaced by the value corresponding to the name "WORD". Case is significant but the trailing semicolon may be omitted if the next character is not a letter, digit, or underscore. By default, these variables look up values inside the environment variables, but can also be defined or redefined within the .signify file itself with a command such as:

     % $email=myid@mycompany.com
 
 

Everything after the equal sign (=) is considered part of the value. Variables can be used in the definition of other variables. As a special case, $$ will evaluate to a single dollar sign ($).

The special variable SIGWIDTH can be used to set the desired output width of the generated signature. By default, this variable has the value "79". There is also a BLANK variable you can place on a line to create a totally empty line when the signature is output.

Including Other Files

You can tell Signify to read another file in place of the current line with a command like:

     % include $HOME/.signify-quotes
 
 

For convienence, you can use a tilde (~) instead of $HOME to read a file relative to your home directory.

Creating Alternates

An unlimited number of "alternates" can be specified by using the "{", "|", and "}" commands. When the signature is generated, only one of all the possible alternates will be output. For example:

     % {
     This is the first possibility.
     % |
     This is the second possibility.
     % |
     This is the third (and last) possibility.
     Note that alternatives can span multiple lines.
     % }
 
 

Creating Columns

Signify will automatically create side-by-side columns with nice, even spacing by using the "(", "|", and ")" commands. When output, everything will be padded out with spaces to fit nicely on the line. For example:

     % (
     This is the
     first column.
     % |
     This is the second.
     % |
     This is the third
     (and last) column.
     % )
 
 

Nesting Sections

Alternates and columns can be nested to any depth, though this can quickly become unwieldy and may not work exactly as expected, especially with columns. As a general rule, only supply alignment options (eg. "center", "right") at the most outside level to do any text formatting. For example, if supplying multiple "alternates" within a column, put the alignment options on the column and not on the alternates.

Section Command Options

The "alternates" and "columns" commands can take options to alter how they behave. The following is a list of supported options and what they do, though not all have meaning for both types of section. Multiple options can be specified by separating them with a comma (,).

bottom

push the following lines of text to the bottom of a column should it have fewer lines than the longest column. This option has no meaning to "alternates" sections.

center

adjust the following lines to be centered on the page or in the column. When used in an "alternates" section, an additional "=<number>" can be used to specify what column to center around instead of the middle of the page.

exec

treat the following lines not as text to be included in the column or alternate, but as commands to be executed by the shell. For each command executed, if its return status is 0 then the output it produced is included at that point, otherwise the output is discarded. Any included text is then aligned, etc. as usual. This command is most useful for inserting random quotes generated by programs such as fortune(6).

left

adjust the following lines so they sit at the left margin. This is the default horizontal alignment and most closely reflects how the lines are entered into the .signify file itself. Note that pad spaces will still be placed on both sides of a column with this type of alignment unless the minwidth option is also specified.

minwidth

do not pad the left and right sides of this column when placing next to other columns. This is useful for building column separator lines and the like that are not really part of the content. This option has no meaning to "alternates" sections.

repeat

output the following lines multiple times to fill all lines in the column. This is useful for building column separator lines and the like that are just a repeated sequence. A multi-line sequence can be specified and only those lines necessary to fill the column will be output. The entire sequence will be output in its entirety at least once, however. This option has no meaning to "alternates" sections.

right

adjust the following lines so they sit at the right margin. Note that pad spaces will still be placed on both sides of a column with this type of alignment unless the minwidth option is also specified.

top

push the following lines of text to the top of a column should it have fewer lines than the longest column. This is the default action if no vertical centering is specified. This option has no meaning to "alternates" sections.

vcenter

push the following lines of text in the vertical center of a column should it have fewer lines than the longest column. This option has no meaning to "alternates" sections.

weight=<number>

change the likelihood a given alternate will be chosen. The chance of any specific alternate being chosen is the given <number> divided by the total of all weights. If not specified, the weight defaults to 1.0. Decimal numbers and numbers less that 1.0 are allowed. This option has no meaning to "columns" sections.

THE COST OF FREE SOFTWARE

Let's face it: Somebody has to pay for all software that gets written. Whether it is the time donated by the programmer or the salary donated by the company, everything has its cost. Signify has been made available to the general public in the hope that it will be useful and thus help raise the visibility of the people that sponsored its creation. In this way, the cost of creating Signify is offset by the publicity gained. If you use this program and would like to further the development of such software, it is asked (but by no means required) that you put something like the following in the quotes section of your .signify file.

     % | center, weight=0.1
     Generated by $PROGRAM.  For this and more, visit $WEBSITE
 
 

(for single-line quote) or (for multi-line in a column)

     % | weight=0.1
     This signature was automatically generated with
     $PROGRAM.  For this and other cool products,
     check out $WEBSITE
 
 

These are weighted very low (though you are more than welcome to increase these weightings :-) and will thus show up in your signature only occasionally. The variables are defined internal to Signify and provide the program name (including version number) and the web site where it can be found. We thank you for your support!

BUGS

Please report any bugs to: bcwhite@pobox.com

AUTHOR

Signify was written and documented by Brian White <bcwhite@pobox.com> on August 24th, 1996.

COPYRIGHT

Signify has been placed in the public domain, the only true "free". It would be apprecated if copies of any improvements or bug-fixes would be sent to the author in order to be incorporated into the main upstream code and propogated to all users of this software.