Replace size_t with int/void* union

I was occasionally passing negative values to size_t.
Plus, this better reflects the intent of the variant argument.

Reported by Coverity:
https://scan8.coverity.com/reports.htm#v13253/p10402/fileInstanceId=22093891&defectInstanceId=7543346&mergedDefectId=174179&fileStart=251&fileEnd=500

1 files changed, 2 insertions, 1 deletions

diff --git a/TraceScreen.c b/TraceScreen.c
index abef7120..845ceaab 100644
--- a/TraceScreen.c
+++ b/TraceScreen.c
@@ -108,7 +108,8 @@ bool TraceScreen_forkTracer(TraceScreen* this) {
       (void) written;
       exit(1);
    }
-   fcntl(this->fdpair[0], F_SETFL, O_NONBLOCK);
+   int ok = fcntl(this->fdpair[0], F_SETFL, O_NONBLOCK);
+   if (ok == -1) return false;
    this->strace = fdopen(this->fdpair[0], "r");
    this->fd_strace = fileno(this->strace);
    return true;