TextTools - General Features
Revised 21-Oct-00. Copyright © 1996-2000 by Rune Berg. TextTools Freeware.

Contents:


The Programs Top

Coloured Responses

As of Release 6, the Win32 executables colour non-functional responses, like banners, error messages, etc.

The colours were chosen to be useful against a black console window background.

You cannot change the colour scheme, but you can turn off colouring by setting an environment variable:

      TTCOLOURS=OFF
The -v Option

Every TextTools program can be invoked with the -v option, e.g.:

      itabs -v
This makes the program print its copyright banner and a brief description of usage and functionality, e.g.:
      itabs v1.20 (BC, Win32, Aug  2 1997) - Copyright (c) 1996-97 by Rune Berg
      
      usage: itabs [log logfile] [options] [infile] [to outfile]
      
      itabs copies infile to outfile, replacing every sequence
      of spaces ending at a tab pos. by a real tab char.
      
      options: -q   Do not insert tabs inside double or single quotes
               -l   Only insert tabs in place of leading spaces
               -nX  Use X (2..128) spaces instead of the default 3
               -nr  Do not print report
               -v   This banner, exit

and then exit with return code 0 (success).

DOS End-of-file Character

TextTools programs never print a DOS end-of-file character (Ctrl-Z, hex 1a) when producing an output file, even if the input file was terminated by such a character. With two exceptions:

Return Codes

Here's a more detailed explanation of the return codes of TextTools programs.

Max. Input Line Length

Most of the TextTools programs read text lines from an input file. The maximum length of such lines is 1024 characters, not counting (carriage return and) newline.

On reading a line that is too long, these programs will print an error message and exit.

Max. Number Of Fields Per Line

For TextTools programs that break input text lines into fields, the maximum number of fields per line is 400.

Floating Point Numbers

General

As of R6, certain TextTools programs (tcols, trows, tsort, tuniq, sum, tand, and tjoin) can recognize, process, and output floating point numbers. These numbers are of the forms:

       3.3  -0.001  3.44e6  1.1e-01

That is, regular "numbers with decimal places" or "scientific format" (where "en" should be read as "times 10 to the power of n").

Applicability

The floating point support in these programs is intended for "everyday" quantities, not rocket science. Little testing has been done to verify the quality of extreme calculations. Specifically, calculations will fail when encountering special values such as +/-NAN and +/-INF.

Theoretically, the range of floating point numbers is (+/-) 1.7e-308 to (+/-) 1.7e+308.
In practice, I recommend you stick to input values and results in the range (+/-) 1.0e-15 to (+/-) 1.0e+20.

Accuracy

By default, floating point calculations, comparisons, intermediate (internal) storage, and output has a precision of six decimal digits. You can, however, adjust this precision to between 0 and 15 decimal digits, using the -fpp option. A precision of, say, 3 digits means that the 4th etc. digits are rounded off: 3.1114 becomes 3.111; 3.1116 becomes 3.112. Note, however, that certain floating point numbers cannot be accurately represented, and may cause border-line case rounding to tilt the wrong way.

Special case: Precision 0 means the number is rounded to the nearest integer (whole) value. The '.' is lost.


The Documentation Top

Understanding The Usage Section

Every TextTools program documentation page has a Usage section, which you should interpret as follows:

Common optional items are:

Upper/lower case for the 'log', 'from', 'and' and 'to' keywords is not significant. Also, these keywords should not be used as file names.

Use Of Colours

Examples of command invokations are shown in a dark red monotype font, e.g.:

      itabs -n5 myinput.txt to myoutput.txt

Examples of input or output data are shown in a dark green monotype font, e.g.:

      7787 "John Smith" London
End of document