unstr(1)

NAME

   strfile - create a random access file for storing strings
   unstr - dump strings in pointer order

SYNOPSIS

   strfile [-iorsx] [-c char] sourcefile [outputfile]
   unstr [-c char] datafile[.ext] [outputfile]

DESCRIPTION

   strfile  reads  a  file  containing groups of lines separated by a line
   containing a single percent `%'  sign  (or  other  specified  delimiter
   character)  and  creates  a data file which contains a header structure
   and a table of file offsets for each group of lines. This allows random
   access of the strings.

   The  output  file,  if  not  specified  on  the  command line, is named
   sourcefile.dat.

   The purpose of unstr is to undo the work of strfile.  It prints out the
   strings  contained in the sourcefile, which is datafile.ext without its
   extension, or datafile if no extension is specified (in this case,  the
   extension  .dat is added to the name of the datafile) in the order that
   they are listed in the header  file  datafile.   If  no  outputfile  is
   specified,  it  prints  to  standard output; otherwise it prints to the
   file specified.   unstr  can  also  universally  change  the  delimiter
   character  in a strings file.  It is possible to create sorted versions
   of input files by using strfile -o and then using unstr  to  dump  them
   out in the table order.

   Options
   The options are as follows:

   -c char
          Change  the  delimiting character from the percent sign to char.
          This option is available for both strfile and unstr.

   -i     Ignore case when ordering the strings.

   -o     Order the strings in alphabetical order.  The offset table  will
          be  sorted  in  the  alphabetical  order  of the groups of lines
          referenced.   Any  initial   non-alphanumeric   characters   are
          ignored.  This  option  causes the STR_ORDERED bit in the header
          str_flags field to be set. (It also now  really  does  sort!  It
          didn't used to).

   -r     Randomize  access  to  the strings.  Entries in the offset table
          will be randomly ordered.  This option causes the STR_RANDOM bit
          in  the  header  str_flags  field  to  be  set. (And really does
          randomize)

   -s     Run silently; don't give a summary message when finished.

   -x     Note that each alphabetic character in the groups  of  lines  is
          rotated  13  positions  in  a simple caesar cypher.  This option
          causes the STR_ROTATED bit in the header str_flags field  to  be
          set.  Note  that  it does not rotate the strings--that operation
          must be performed separately.

   Header
   The format of the header is:

   #define VERSION 1
   unsigned long str_version;  /* version number */
   unsigned long str_numstr;   /* # of strings in the file */
   unsigned long str_longlen;  /* length of longest string */
   unsigned long str_shortlen; /* shortest string length */
   #define STR_RANDOM    0x1   /* randomized pointers */
   #define STR_ORDERED   0x2   /* ordered pointers */
   #define STR_ROTATED   0x4   /* rot-13'd text */
   unsigned long str_flags;    /* bit field for flags */
   char str_delim;             /* delimiting character */

   All fields are written in network byte order.

BUGS

   Fewer now, one hopes.  However, fortunes (text strings) beginning  with
   a blank line appear to be sorted between random letters.  This includes
   ASCII art that contains no letters, and first  lines  that  are  solely
   non-alphanumeric, apparently.  I've no idea why this should be.

OTHER USES

   What  can  you  do  with  this  besides  printing sarcastic and obscene
   messages to the screens of lusers at login or logout?

   There are some other possibilities.  Source code for a sample  program,
   randstr,  is  included  with  this  distribution:  randstr  splits  the
   difference between unstr and fortune.  It  reads  a  single,  specified
   file, and randomly selects a single text string.

   1      Include  strfile.h  into  a  news  reading/posting  program,  to
          generate random signatures.  Tin(1) does something similar, in a
          much more complex manner.

   2      Include it in a game.  While strfile doesn't support 'fields' or
          'records', there's no reason that  the  text  strings  can't  be
          consistent:  first line, a die roll; second line, a score; third
          and subsequent lines, a text message.

   3      Use it to store your address book.  Hell, some  of  the  guys  I
          know  would  be  as  well  off using it to decide who to call on
          Friday nights (and for some, it wouldn't  matter  whether  there
          were phone numbers in it or not).

   4      Use  it  in  'lottery'  situations.   If  you're an ISP, write a
          script to store  login  names  and  GECOS  from  /etc/passwd  in
          strfile  format,  write another to send 'congratulations, you've
          won' to the lucky login selected.  The prize might be a  month's
          free  service,  or if you're AOL, a month free on a real service
          provider.

SEE ALSO

   byteorder(3), fortune(6)

HISTORY

   The strfile utility first appeared in 4.4BSD. This version was  heavily
   modified,  much  of  it in ways peculiar to Linux.  Work has since been
   done to make the code more generic, and has so far been tested to  work
   with  SunOS  4.x.   More platforms are expected to be supported as work
   continues.

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