[clang] [clang][analyzer] StreamChecker: Model getc, vfscanf, putc, vfprintf (PR #82476)

[Balázs Kéri via cfe-commits]

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@@ -339,3 +363,138 @@ void fflush_on_open_failed_stream(void) {
   }
   fclose(F);
 }
+
+void test_fscanf_eof() {
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balazske wrote:

Has this test a purpose that is different from test `error_fscanf` in **stream_error.c**?

https://github.com/llvm/llvm-project/pull/82476