+/**
+ * xopen() is the same as open(), but it die()s if the open() fails.
+ */
+int xopen(const char *path, int oflag, ...)
+{
+ mode_t mode = 0;
+ va_list ap;
+
+ /*
+ * va_arg() will have undefined behavior if the specified type is not
+ * compatible with the argument type. Since integers are promoted to
+ * ints, we fetch the next argument as an int, and then cast it to a
+ * mode_t to avoid undefined behavior.
+ */
+ va_start(ap, oflag);
+ if (oflag & O_CREAT)
+ mode = va_arg(ap, int);
+ va_end(ap);
+
+ for (;;) {
+ int fd = open(path, oflag, mode);
+ if (fd >= 0)
+ return fd;
+ if (errno == EINTR)
+ continue;
+
+ if ((oflag & O_RDWR) == O_RDWR)
+ die_errno(_("could not open '%s' for reading and writing"), path);
+ else if ((oflag & O_WRONLY) == O_WRONLY)
+ die_errno(_("could not open '%s' for writing"), path);
+ else
+ die_errno(_("could not open '%s' for reading"), path);
+ }
+}
+