Landon Curt Noll
4ee4c731f7
While not strictly necessary, replacing the two ASCII tab characters in the markdown copyright comment makes it easier to detect problematic TAB indentation within markdown files. After this commit, only 90 markdown files have leading ASCII TAB characters. And again, while not strictly necessary, we can consider running expand on those 90 markdown files to see what effect that might have on the HTML files they produce. Replace leading ASCII TAB characters with multiples of 8 ASCII SPACE characters (the default action of the `expand(1)` tool) might have an negative effect on some HTML formatting where **hack-a-round** formatting was attempted to fix broken indentation caused by problematic ASCII TAB characters. Think of this as a baseline for evaluating leading TAB characters within markdown files. TODO: Consider either using `expand(1)` to replace leading ASCII TAB characters with multiples of 8 ASCII SPACE characters AND/OR modifying the appropriate `bin` tool to convert leading ASCII TAB characters into multiples of 8 ASCII SPACE characters.
To build:
make all
```
## To use:
``` <!---sh-->
./wall
# enter some numbers
./wall | some_command
# enter some strings or numbers, depending on command
Try:
./try.sh
You may of course run the commands manually and enter text as you wish. For instance you might try one or both of:
./wall | bc
./wall | cat
and enter some input like:
x*x
2^x
quit # for the cat version
which the script does through a pipeline except that here you can enter more text if you wish, line by line.
Judges' remarks:
What we found amazing was how the flow of control was transferred between
subroutines. Careful inspection will show that the array of pointers to
functions named vi refers to functions which seem to not be directly called.
Even so, these pointers to functions are being used as an argument to
signal(3) (used both with and without an arg - but how?). Can you determine
why this is being done and how it is being exploited?
Some compilers complained about this file, so we changed: =++I to = ++I.
Author's remarks:
No remarks were provided by the author.