(coreutils.info.gz) Compatibility in ptx

Info Catalog

(coreutils.info.gz) Output formatting in ptx

(coreutils.info.gz) ptx invocation

 
 7.5.5 The GNU extensions to 'ptx'
 ---------------------------------
 
 This version of 'ptx' contains a few features which do not exist in
 System V 'ptx'.  These extra features are suppressed by using the '-G'
 command line option, unless overridden by other command line options.
 Some GNU extensions cannot be recovered by overriding, so the simple
 rule is to avoid '-G' if you care about GNU extensions.  Here are the
 differences between this program and System V 'ptx'.
 
    * This program can read many input files at once, it always writes
      the resulting concordance on standard output.  On the other hand,
      System V 'ptx' reads only one file and sends the result to standard
      output or, if a second FILE parameter is given on the command, to
      that FILE.
 
      Having output parameters not introduced by options is a dangerous
      practice which GNU avoids as far as possible.  So, for using 'ptx'
      portably between GNU and System V, you should always use it with a
      single input file, and always expect the result on standard output.
      You might also want to automatically configure in a '-G' option to
      'ptx' calls in products using 'ptx', if the configurator finds that
      the installed 'ptx' accepts '-G'.
 
    * The only options available in System V 'ptx' are options '-b',
      '-f', '-g', '-i', '-o', '-r', '-t' and '-w'.  All other options are
      GNU extensions and are not repeated in this enumeration.  Moreover,
      some options have a slightly different meaning when GNU extensions
      are enabled, as explained below.
 
    * By default, concordance output is not formatted for 'troff' or
      'nroff'.  It is rather formatted for a dumb terminal.  'troff' or
      'nroff' output may still be selected through option '-O'.
 
    * Unless '-R' option is used, the maximum reference width is
      subtracted from the total output line width.  With GNU extensions
      disabled, width of references is not taken into account in the
      output line width computations.
 
    * All 256 bytes, even ASCII NUL bytes, are always read and processed
      from input file with no adverse effect, even if GNU extensions are
      disabled.  However, System V 'ptx' does not accept 8-bit
      characters, a few control characters are rejected, and the tilde
      '~' is also rejected.
 
    * Input line length is only limited by available memory, even if GNU
      extensions are disabled.  However, System V 'ptx' processes only
      the first 200 characters in each line.
 
    * The break (non-word) characters default to be every character
      except all letters of the underlying character set, diacriticized
      or not.  When GNU extensions are disabled, the break characters
      default to space, tab and newline only.
 
    * The program makes better use of output line width.  If GNU
      extensions are disabled, the program rather tries to imitate System
      V 'ptx', but still, there are some slight disposition glitches this
      program does not completely reproduce.
 
    * The user can specify both an Ignore file and an Only file.  This is
      not allowed with System V 'ptx'.
 

Info Catalog

(coreutils.info.gz) Output formatting in ptx

(coreutils.info.gz) ptx invocation