GUILE_DLSYM_USCORE
-AC_CHECK_FUNCS(ctermid ftime getcwd geteuid gettimeofday lstat mkdir mknod nice readlink rename rmdir select setegid seteuid setlocale setpgid setsid sigaction strftime strptime symlink sync tcgetpgrp tcsetpgrp times uname waitpid bzero strdup system usleep atexit)
+AC_CHECK_FUNCS(ctermid ftime getcwd geteuid gettimeofday lstat mkdir mknod nice readlink rename rmdir select setegid seteuid setlocale setpgid setsid sigaction strftime strptime symlink sync tcgetpgrp tcsetpgrp times uname waitpid bzero strdup system usleep atexit on_exit)
### Some systems don't declare some functions. On such systems, we
### need to at least provide our own K&R-style declarations.