reorganize

src/getlogin.c

@@ -0,0 +1,42 @@
+/*
+ * getlogin.c
+ *
+ * Print information on login name and terminal, to demonstrate
+ * the thread-safe functions.
+ */
+#include <limits.h>
+#include "errors.h"
+
+/*
+ * If either TTY_NAME_MAX or LOGIN_NAME_MAX are undefined
+ * (this means they are "indeterminate" values), assume a
+ * reasonable size (for simplicity) rather than using sysconf
+ * and dynamically allocating the buffers.
+ */
+#ifndef TTY_NAME_MAX
+# define TTY_NAME_MAX    128
+#endif
+#ifndef LOGIN_NAME_MAX
+# define LOGIN_NAME_MAX  32
+#endif
+    
+int main (int argc, char *argv[])
+{
+    char login_str[LOGIN_NAME_MAX];
+    char stdin_str[TTY_NAME_MAX];
+    char cterm_str[L_ctermid], *cterm_str_ptr;
+    int status;
+
+    status = getlogin_r (login_str, sizeof (login_str));
+    if (status != 0)
+        err_abort (status, "Get login");
+    cterm_str_ptr = ctermid (cterm_str);
+    if (cterm_str_ptr == NULL)
+        errno_abort ("Get cterm");
+    status = ttyname_r (0, stdin_str, sizeof (stdin_str));
+    if (status != 0)
+        err_abort (status, "Get stdin");
+    printf ("User: %s, cterm: %s, fd 0: %s\n",
+        login_str, cterm_str, stdin_str);
+    return 0;
+}