File format (cont.)

[Harold W. Baldwin]

I'm writing this primarily to help with some of the file format
documentation, but I also want to thank Pete for his fix of the file format
setting bug.  Pete's fix brought io-term.c up to revision 1.54 and since I
had version 1.52, I just replaced my version with 1.54 and remade oleo.

"M-x set-option RET file <file_format> RET" works pretty well now, except
when I try to specify either panic or csv as the format.  In both cases I
get an "unknown file format" message, but I don't think this is
particularly crucial.  "Panic" seems to be a pretty rare and specialized
format.  And I believe I saw somewhere in the sources that "csv" is just an
alias for the list format with commas used to separate the values in the
cells, but this format can be achieved by first setting the file format to
"list" and then changing the separator to a comma.

In the documentation under section 6, Options, subsection 6.1, Changing
Oleo's Appearance, there is the following entry about how to change the
separator: 
  list (ch)  Use the character CH to separate the cell values (18)
(18) is a link to a footnote which raises a question about just what
should be entered to change the separator.  Here's the answer:  To set the
separator to, for instance, a comma, enter:
  M-x set-option RET list ,
To set it to a control character, e.g., ^I (which is the default), enter:
  M-x set-option RET list \11
The number to be used is the ASCII value of the control character desired.
Note that the separator could also be set to, e.g., the letter z.

To retrieve a file which uses some separator, s, be sure the filename has
the suffix .list on it, start oleo, set the file type to list and the
separator to s ("M-x set-option RET file list RET", and then "M-x
set-option RET list s RET"), and then read in the file.  This is what
would need to be done if, e.g., the letter z were used as a separator.  
However, there are at least 2 cases where these options don't need to be
set: if the file uses (1) a comma or (2) a tab as a separator, then if the
filename has the suffix (1) .csv or (2) .list, then it will be read in
without having to set the options.  Note that if the file is then saved,
it will be saved in oleo format, so to read it back in properly, the
suffix will need to be removed or changed to .oleo.

                      - Wes Baldwin