Diffstat (limited to 'modules/pam_filter/pam_filter.h')
1 files changed, 32 insertions, 0 deletions
diff --git a/modules/pam_filter/pam_filter.h b/modules/pam_filter/pam_filter.h
new file mode 100644
@@ -0,0 +1,32 @@
+ * $Id$
+ * this file is associated with the Linux-PAM filter module.
+ * it was written by Andrew G. Morgan <firstname.lastname@example.org>
+ * this will fail if there is some problem with these file descriptors
+ * being allocated by the pam_filter Linux-PAM module. The numbers
+ * here are thought safe, but the filter developer should use the
+ * macros, as these numbers are subject to change.
+ * The APPXXX_FILENO file descriptors are the STDIN/OUT/ERR_FILENO of the
+ * application. The filter uses the STDIN/OUT/ERR_FILENO's to converse
+ * with the user, passes (modified) user input to the application via
+ * APPIN_FILENO, and receives application output from APPOUT_FILENO/ERR.
+#define APPIN_FILENO 3 /* write here to give application input */
+#define APPOUT_FILENO 4 /* read here to get application output */
+#define APPERR_FILENO 5 /* read here to get application errors */
+#define APPTOP_FILE 6 /* used by select */