(recode.info)Dump

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Interpreted character dumps
===========================

   Dumps are surfaces meant to express, in ways which are a bit more
readable, the bit patterns used to represent characters.  They allow
the inspection or debugging of character streams, but also, they may
assist a bit the production of C source code which, once compiled,
would hold in memory a copy of the original coding.  However, `recode'
does not attempt, in any way, to produce complete C source files in
dumps.  User hand editing or `Makefile' trickery is still needed for
adding missing lines.  Dumps may be given in decimal, hexadecimal and
octal, and be based over chunks of either one, two or four eight-bit
bytes.  Formatting has been chosen to respect the C language syntax for
number constants, with commas and newlines inserted appropriately.

   However, when dumping two or four byte chunks, the last chunk may be
incomplete.  This is observable through the usage of narrower expression
for that last chunk only.  Such a shorter chunk would not be compiled
properly within a C initialiser, as all members of an array share a
single type, and so, have identical sizes.

`Octal-1'
     This surface corresponds to an octal expression of each input byte.

     It is available in `recode' under the name `Octal-1', with `o1'
     and `o' as acceptable aliases.

`Octal-2'
     This surface corresponds to an octal expression of each pair of
     input bytes, except for the last pair, which may be short.

     It is available in `recode' under the name `Octal-2' and has `o2'
     for an alias.

`Octal-4'
     This surface corresponds to an octal expression of each quadruple
     of input bytes, except for the last quadruple, which may be short.

     It is available in `recode' under the name `Octal-4' and has `o4'
     for an alias.

`Decimal-1'
     This surface corresponds to an decimal expression of each input
     byte.

     It is available in `recode' under the name `Decimal-1', with `d1'
     and `d' as acceptable aliases.

`Decimal-2'
     This surface corresponds to an decimal expression of each pair of
     input bytes, except for the last pair, which may be short.

     It is available in `recode' under the name `Decimal-2' and has
     `d2' for an alias.

`Decimal-4'
     This surface corresponds to an decimal expression of each
     quadruple of input bytes, except for the last quadruple, which may
     be short.

     It is available in `recode' under the name `Decimal-4' and has
     `d4' for an alias.

`Hexadecimal-1'
     This surface corresponds to an hexadecimal expression of each
     input byte.

     It is available in `recode' under the name `Hexadecimal-1', with
     `x1' and `x' as acceptable aliases.

`Hexadecimal-2'
     This surface corresponds to an hexadecimal expression of each pair
     of input bytes, except for the last pair, which may be short.

     It is available in `recode' under the name `Hexadecimal-2', with
     `x2' for an alias.

`Hexadecimal-4'
     This surface corresponds to an hexadecimal expression of each
     quadruple of input bytes, except for the last quadruple, which may
     be short.

     It is available in `recode' under the name `Hexadecimal-4', with
     `x4' for an alias.

   When removing a dump surface, that is, when reading a dump results
back into a sequence of bytes, the narrower expression for a short last
chunk is recognised, so dumping is a fully reversible operation.
However, in case you want to produce dumps by other means than through
`recode', beware that for decimal dumps, the library has to rely on the
number of spaces to establish the original byte size of the chunk.

   Although the library might report reversibility errors, removing a
dump surface is a rather forgiving process: one may mix bases, group a
variable number of data per source line, or use shorter chunks in
places other than at the far end.  Also, source lines not beginning
with a number are skipped.  So, `recode' should often be able to read a
whole C header file, wrapping the results of a previous dump, and
regenerate the original byte string.