As betterworld said: you can just croak() from C and it'll throw an exception in the calling perl code. This, or returning undef/false, is almost always what you want to do.

You can set $! from C, but you should probably only do so under very limited circumstances. $! is tied directly to the C macro errno which is almost exclusively used for IO errors. Look it up. Note that errno is a number.

"What should it profit a man, if he should win a flame war, yet lose his cool?"

In reply to Re: Propagating errors in C code to Perl by Joost
in thread Propagating errors in C code to Perl by missingthepoint

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