use libblkid to get filesystem type
we can now use libblkid to detect exfat
diff --git a/libblkid/exec_shell.c b/libblkid/exec_shell.c
new file mode 100644
index 0000000..95620cd
--- /dev/null
+++ b/libblkid/exec_shell.c
@@ -0,0 +1,27 @@
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/types.h>
+
+#include "nls.h"
+#include "c.h"
+#include "xalloc.h"
+
+#include "exec_shell.h"
+
+#define DEFAULT_SHELL "/bin/sh"
+
+void __attribute__((__noreturn__)) exec_shell(void) {
+ const char *shell = getenv("SHELL"), *shell_basename;
+ char *arg0;
+ if (!shell)
+ shell = DEFAULT_SHELL;
+
+ shell_basename = basename(shell);
+ arg0 = xmalloc(strlen(shell_basename) + 2);
+ arg0[0] = '-';
+ strcpy(arg0 + 1, shell_basename);
+
+ execl(shell, arg0, NULL);
+ err(EXIT_FAILURE, _("failed to execute %s"), shell);
+}