STRFILE(1) UNIX System Manager's Manual STRFILE(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 off
sets 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 out_
putfile is specified, it prints to standard output; other
wise it prints to the file specified. unstr can also uni
versally 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 off
set 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 distribu
tion: randstr splits the difference between unstr and for
tune. It reads a single, specified file, and randomly
selects a single text string.
1 Include strfile.h into a news reading/posting pro
gram, 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 sup
port '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 subse
quent 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 ALSObyteorder(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.
4th Berkeley DistribuJune 9, 1993 [Apr. '97] STRFILE(1)
