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Format fix 2000/schneiderwent/README.md

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Cody Boone Ferguson committed 2023-04-20 12:35:23 -07:00
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@@ -19,8 +19,11 @@ make
```sh
./schneiderwent schneiderwent.data
./schneiderwent
```
What's the difference?
## Judges' remarks:
Very nice play by the rules and portable text obfuscation.
@@ -35,46 +38,43 @@ keeping the program portable between different encodings
This entry displays the current time to the console, for example:
it's just after ten 'til 6 in the evening
> it's just after ten 'til 6 in the evening
FWIW, none of the compilers with which this entry was tested issued
any warnings or errors in compiling the source for this entry. No
doubt lint will complain about the goto statements.
The schneiderwent.data file consists of the values used by multiple
table lookups. This is simply good program design, separating
these values from the source code allows changing the behavior of
the application without recompiling.
The [schneiderwent.data](schneiderwent.data) file consists of the values used by
multiple table lookups. This is simply good program design, separating these
values from the source code allows changing the behavior of the application
without recompiling.
Having learned COBOL at an early age, the pthreads of my thought
Having learned COBOL at an early age, the `pthread`s of my thought
processes tend to be translated into code in a verbose manner. Some
of the #defines in this entry's code are to mitigate this personal
of the `#define`s in this entry's code are to mitigate this personal
deficiency.
### Obfuscation
Obfuscation in this entry consists of:
* printfing console messages stored as EBCDIC character values - this is not an
attempt at encryption, but rather at cross platform compatibility
* `printf()`ing console messages stored as EBCDIC character values - this is not
an attempt at encryption, but rather at cross platform compatibility.
* ASCII character values are calculated from the EBCDIC in a particularly ugly
abuse of the '?' operator
* detection of whether to print the ASCII or EBCDIC values is done by taking the
remainder of dividing the character 'J' by 2 - the ASCII value of the character
is even, the EBCDIC value is odd
* the messages to be printfed are determined via multiple table lookups and
bitmasked values
* for minutes, the bit position turned on is multiplied by two to determine the
message to be printfed
* for hours, the straight bit position is used
* this entry mostly eschews function calls for the often overlooked
setjmp/longjmp combination
* the trigraphs are not there as obfuscation nor are they there to annoy the
abuse of the '?' operator.
* Detection of whether to print the ASCII or EBCDIC values is done by taking the
remainder of dividing the character `'J'` by `2` - the ASCII value of the
character is even, the EBCDIC value is odd.
* The messages to be `printf`ed are determined via multiple table lookups and
bit-masked values.
* For minutes, the bit position turned on is multiplied by two to determine the
message to be `printf`ed.
* For hours, the straight bit position is used.
* This entry mostly eschews function calls for the often overlooked
setjmp/longjmp combination.
* The trigraphs are not there as obfuscation nor are they there to annoy the
judges - it's just the easiest way to get around the absence of square brackets
in a normal 3270 environment
in a normal 3270 environment.
## Copyright and CC BY-SA 4.0 License: