Provided by: slice_1.3.8-11_all bug


       Slice -- Extract pre-defined slices from an ASCII file


       slice [-v] [-y outputpolicy] [-o
       sliceterm:outputfile[@chmodcmd][#outputpolicy] ..]  [inputfile]

       slice [-V] [-h]


       1.3.8 (10-Feb-2002)


   Input Principle
       The slice program reads inputfile (or from STDIN if inputfile is not
       given or equal ``"-"'') and divides its already prepared ASCII contents
       into possibly overlapping areas, called slices.   These slices are
       determined by enclosing blocks defined by begin and end delimiters
       which have to be already in the file. These block delimiters use the

         [NAME: ... :NAME]

       or alternatively (if there is no misinterpretation possible, i.e. no
       overlapping or stacked slices)

         [NAME: ... :]

       The NAME identifier has to match against the regular expression
       ``"[_A-Z0-9]+"'', i.e. NAME is a string consisting only of uppercase
       letters, digits or underscore characters.

       There can be as many such slice definitions as you like and there can
       be more than one slice with the same name. The resulting slice is the
       union of all equal named slices. Actually use this to spread a big
       slice over disjunct peaces of inputfile.

   Output Selection Scheme
       The final output data gets calculated by a slice term consisting of
       slice names and set theory operators. The following syntax is
       recognized (in order of LR(1) grammar parsing) for slice terms:

       SLICE_TERM ::= "NAME"
           The slice NAME itself. This name has to match against the regex
           ``"[_A-Z0-9*{}]+"''. Here two cases are possible: "NAME" is either
           a plain slice name consisting only of uppercase letters, digits or
           an underscore character. Or it is a wildcarded slice name indicated
           by an asterisk character.

           The first variant just expands to the union of all slices named
           exactly "NAME".  The second variant expands to the union of all
           slices which match against the wildcard pattern "NAME". Here the
           asterisk has the semantical meaning of none or any number of
           characters.  There is one special case, when the asterisk is
           immediately followed by characters enclosed within braces, it means
           none or any number of characters, but not this sequence of

       SLICE_TERM ::= "!NAME" | "~NAME"
           The complement of slice NAME (i.e. ALL\NAME).

           In formula: {x in ALL: x not in NAME}

       SLICE_TERM ::= "NAME1xNAME2", "NAME1^NAME2"
           The exclusive-or relation between slice NAME1 and slice NAME2. In
           set theory also called symmetric difference:
           (NAME1uNAME2)\(NAME1nNAME2) or alternatively

           In formula: {x in ALL: (x in NAME1 or x in NAME2) and not (x in
           NAME1 and x in NAME2)}.

       SLICE_TERM ::= "NAME1\NAME2", "NAME1-NAME2"
           The difference of slice NAME1 and slice NAME2, i.e. NAME1 minus

           In formula: {x in ALL: x in NAME1 and x not in NAME2}

       SLICE_TERM ::= "NAME1nNAME2" | "NAME1%NAME2"
           The intersection of slice NAME1 and slice NAME2.

           In formula: {x in ALL: x in NAME1 and x in NAME2}

       SLICE_TERM ::= "NAME1uNAME2", "NAME1+NAME2"
           The union of slice NAME1 and slice NAME2.

           In formula: {x in ALL: x in NAME1 or x in NAME2}

       SLICE_TERM ::= "(" SLICE_TERM ")"
           A grouped slice term. Use this to force a different order of
           evaluation.  By default, all operators are left-associative, except
           complement which is right-associative.  Operators are listed below
           from lowest to highest precedence:

               -  u  x  n  !

   Advanced Selection: Slice Levels
       Because slices can be overlapping and stacked, a definition level is
       assigned to each slice while the input is parsed. These levels range
       from 1 to the maximum encountered (the level 0 is the whole file, i.e.
       "ALL").  When a slice begins, it is assigned the lowest free level,
       beginning with level 1. As long as one level is in use, it cannot be
       assigned again until the end delimiter of the corresponding slice is

       An example:


         3                     E-----------E
         2      B--B        D--------D
         1   A--------A  C--------C     F-----F

       Here slice A is assigned level 1. Then B is assigned level 2 because
       level 1 is still in use by A. Then the end of B is reached, level 2 is
       freed.  Then the end of A is reached and level 1 is also free now, so C
       is assigned level 1 again. Now only level 1 is in use, so D is assigned
       level 2. Then E is assigned level 3. Then the end of C is seen and
       level 1 freed. Then the end of D is seen and level 2 is freed. Now F
       begins and because only level 3 is in use, it gets level 1 assigned.
       Then the end of E frees level 3 and the end of F frees level 1. Finally
       no levels are still in use. This indicates that the slicing is correct.

       If there are any used levels left at the end of this process this
       indicates an input error and slice responds with an error message
       displaying the still open slices.

       This complicated level mechanism is needed for granular set operations
       where particular slices should be included or excluded only. So, to
       make life easier, a few pseudo-slices are automatically defined:

           The union of all user-defined slices at exactly level n (0 <= n <=

           The union of all non-user-defined slices at exactly level n (0 <= n
           <= oo).  This actually is just "!DEFn".

           The union of all user-defined slices at all levels, beginning at
           level 1.  This actually is the union of all "DEFn" slices.

           The union of all non-user-defined slices at all levels, beginning
           with 1. This actually is just "!DEF".

           The whole file. This actually is just "UNDEF0", because at level 0
           there are no user defined slices, so all is undefined.

           This is the slice NAME minus the union of all "DEFn" slices with
           min(NAME) <= n <= oo. Here min(NAME) is the lowest level plus one
           where NAME ever occurred.  You can read this as ``NAME without all
           other slices at higher levels which overwrite it''. This sounds a
           little bit crazy, but actually is the most important construct. Try
           to understand it or your slice terms become very complicated.


       [-y outputpolicy]
           This flag changes output policy depending on events: "u" when an
           undefined set is encountered, "w" for an unmatched wildcard set,
           "z" when output is empty and "s" if it only consists of whitespace
           characters.  Each letter is followed by a digit telling which
           action is bound to such events: 0 to ignore such events, 1 to
           display a warning message and continue, 2 to skip concerned file
           and continue, and 3 to abort with an error message.

           This flag consists of one or more events specifications, and
           default is "u0w0s0z0".

       [-o sliceterm:outputfile[@chmodcmd][#outputpolicy] ..]
           This redirects the output to a file. Usually the whole file will be
           send to "STDOUT" (same as "ALL:-"). You can use this option more
           than once to output to more than one file while the corresponding
           sliceterm determines which output data will be included into each
           output file.

           The optional chmodcmd string is intended for specifying options for
           the chmod command, which is applied to outputfile after writing.
           For instance use ``"a+r"'' to make sure the file is readable by a
           webserver of ``"u+x"'' to create a file with the execution bit set
           (usually used for SSI files on a webserver with the "XBitHack"
           option available).

           The optional outputpolicy string allows changing output policy for
           only this output file without changing its global meaning.  See
           above for information on output policy.

           Be careful here: When you use parenthesis or asterisks inside
           sliceterm you have to make sure it is really passed to slice this
           way, i.e. usually you have to escape these characters from
           interpolation by the used shell. Do this either by adding
           backslashes in front of these characters or just surround the
           complete option argument with single quotes ('').

       -v  This sets verbose mode where some processing information will be
           given on the console for debugging purpose.

       -V  Displays the version identification string.

       -h  Displays the usage page.


       Sometimes it can be very useful to be able to provide command line
       options directly within the input file, for instance to setup one or
       more -o options. For this slice recognizes lines of the form

          %!slice OPTIONS

       in the input file and automatically adds OPTIONS to the argument line
       options.  These lines have to start in column 0.


          %!slice -oTOC:contents.txt


       Assume the following simple multi-language article file article.src,
       written in HTML:


         <h1>[EN:The Title itself:][DE:Der Titel selbst:]</h1>

         [EN:...English Abstract...:]
         [DE:...Deutsche Zusammenfassung...:]

         [EN:...English Text...:]
         [DE:...Deutscher Text...:]


       The command

         slice -o ENuUNDEF:article.html.en -o

       then creates the following to files:


             <h1>The Title itself</h1>

             ...English Abstract...

             ...English Text...

             <h1>Der Titel selbst</h1>

             ...Deutsche Zusammenfassung...

             ...Deutscher Text...


       The current implementation only handles anonymous end delimiters
       ``":]"'' correct in clear cases where no mis-interpretation is
       possible, i.e. when no overlapping occurs. For instance in


       the end delimiter is not correctly assign to the `B' slice. So, be
       careful when using anonymous end delimiters in overlapping situations.
       Pure stacking like


       is allowed and handled correctly, but only when you interpret this as



         Copyright (c) 1997-2002 Ralf S. Engelschall.
         Copyright (c) 1999-2002 Denis Barbier.


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         Ralf S. Engelschall

         Denis Barbier