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[@safe printf] Minor tweaks #2

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9 changes: 4 additions & 5 deletions SafePrintf.md
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Expand Up @@ -45,12 +45,11 @@ builds.

The unsafe problems with printf are:

1. mismatch of arguments with format specifiers. This is mitigated by the compiler's
checks for those mismatches
1. mismatch of arguments with format specifiers. These are detected by `pragma(printf)`.
2. the %s takes as an argument a pointer to a string. While the string is only read,
the pointer still walks the string in an unbounded manner
3. the %.*s parameter takes an argument of the form (int,char*). The int is the number
of characters to print, but a value <=0 has unsafe behavior
of characters to print, but a value < 0 has unsafe behavior
4. a format string that is not a literal and the compiler cannot check it

These are fixable problems, or can be constrained so they are memory safe.
Expand All @@ -73,8 +72,8 @@ specifier to be rewritten to match the argument type, if the format specifier
is `%s`.

If the format specifier is `%s` and the corresponding argument is a D array of char
or wchar_t, the format will
be replace with `%.*s` (or `%.*ls`) and the argument will be replaced with two arguments of
or wchar_t, the specifier will
be replaced with `%.*s` (or `%.*ls`) and the argument will be replaced with two arguments of
the form:

```
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