xp_fail
bool xp_fail(int, const char *, ...) __printflike(2, 3);
xp_fail(__LINE__, fmt); \
r = xp_fail(line, "%s expects %d but %d", varname, exp, act);
r = xp_fail(line, "%s expects \"%s\" but \"%s\"",
r = xp_fail(line, "%s expects != %d but %d", varname, exp, act);
r = xp_fail(__LINE__, "(%s) is expected but not met", exprname);
r = xp_fail(line, "%s expects %d but -1,err#%d(%s)",
r = xp_fail(line, "%s expects success but -1,err#%d(%s)",
r = xp_fail(line, "%s expects -1,err#%d but %d",
r = xp_fail(line, "%s expects -1,err#%d(%s) but -1,err#%d(%s)",
r = xp_fail(line,
r = xp_fail(line,
r = xp_fail(line,