Re^2: sprintf and arrays of unknown (in advance) length

> What happens when perl ... "runs out" of parameters

Note that C behaves the same, but bash doesn't:

$ printf '[%s]' two strings
[two][strings]
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($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,
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Re^3: sprintf and arrays of unknown (in advance) length by Anonymous Monk on Oct 12, 2018 at 11:34 UTC
Curious: I couldn't get an example C program calling `printf("%s\n", "two", "strings");` to crash or display any errors under Valgrind or `-fsanitize=address -fsanitize=undefined` even with full optimization and with omitted frame pointers, despite it being undefined behaviour. Not passing enough arguments in C for `%s`, though, causes a crash pretty quickly, because `printf` tries to interpret as a pointer something that was left on the stack from a previous function call, whatever it was. I got a lucky `(null)` a few times (stack had been filled with zeroes, and some C libraries handle `NULL` for `%s` as a special case, which is not required by the standard), then crashed on a different run when it tried to dereference address `0x1`.	[reply] [d/l] [select]

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Re^3: sprintf and arrays of unknown (in advance) length
by Anonymous Monk on Oct 12, 2018 at 11:34 UTC

Curious: I couldn't get an example C program calling printf("%s\n", "two", "strings"); to crash or display any errors under Valgrind or -fsanitize=address -fsanitize=undefined even with full optimization and with omitted frame pointers, despite it being undefined behaviour.

Not passing enough arguments in C for %s, though, causes a crash pretty quickly, because printf tries to interpret as a pointer something that was left on the stack from a previous function call, whatever it was. I got a lucky (null) a few times (stack had been filled with zeroes, and some C libraries handle NULL for %s as a special case, which is not required by the standard), then crashed on a different run when it tried to dereference address 0x1.

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