Hi, I'm not a C expert, but I see there is a use of an unitialized variable: default: { int got, exitstatus = 0; int ret; char status; close(statuspipe[1]); /* We wait to make sure the first child forked successfully */ if ((got = waitpid(pid, &exitstatus, 0)) < 0 || got != pid || status != 0) { <<< here return -1; } That explains the issue described by Guido, because he uses an i386 system. It was impossible for me to reproduce the issue because I use an amd64 system. char test; if (test == 0) puts("ok"); else puts("ko"); produces: - "ok" on amd64 system - "ko" on i386 system If I use the exitstatus variable in the test it seems to work great on both architectures. -- Laurent Léonard