X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=ipc.c;h=85013a636cb3a7f634d190d9044808454274efd8;hp=9488224a1d4a622860adc957b27977e2bcbfc7e2;hb=f8cc8caab7176a65731520f3130dc059e5d5773e;hpb=68630d8b55d688a7c7ce116951c310150aa9c166

diff --git a/ipc.c b/ipc.c
index 9488224a..85013a63 100644
--- a/ipc.c
+++ b/ipc.c
@@ -1,8 +1,4 @@
-/*
- * Copyright (C) 2006 Andre Noll <maan@tuebingen.mpg.de>
- *
- * Licensed under the GPL v2. For licencing details see COPYING.
- */
+/* Copyright (C) 2006 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
 
 /** \file ipc.c Inter-process communication and shared memory helpers. */
 
@@ -68,7 +64,7 @@ static void para_semop(int id, struct sembuf *sops, int num)
  *
  * This function either succeeds or aborts.
  *
- * \sa semop(2), struct misc_meta_data.
+ * \sa semop(2), struct \ref misc_meta_data.
  */
 void mutex_lock(int id)
 {
@@ -94,7 +90,7 @@ void mutex_lock(int id)
  *
  * This function either succeeds or aborts.
  *
- * \sa semop(2), struct misc_meta_data.
+ * \sa semop(2), struct \ref misc_meta_data.
  */
 void mutex_unlock(int id)
 {
@@ -161,6 +157,27 @@ int shm_attach(int id, enum shm_attach_mode mode, void **result)
 	return *result == (void *) -1? -ERRNO_TO_PARA_ERROR(errno) : 1;
 }
 
+/**
+ * Get the size of a shared memory segment.
+ *
+ * \param id The shared memory segment identifier.
+ * \param result Size in bytes is returned here, zero on errors.
+ *
+ * \return Standard.
+ *
+ * \sa shmctl(2).
+ */
+int shm_size(int id, size_t *result)
+{
+	struct shmid_ds ds; /* data structure */
+
+	*result = 0;
+	if (shmctl(id, IPC_STAT, &ds) < 0)
+		return -ERRNO_TO_PARA_ERROR(errno);
+	*result = ds.shm_segsz;
+	return 1;
+}
+
 /**
  * Detach a shared memory segment.
  *