Corrected error codes in doxygen function doc; corrected problem with return value when using write key function for shared values

5 files changed, 123 insertions, 86 deletions

diff --git a/include/persistence_client_custom.h b/include/persistence_client_custom.h
index 3fc894e..56f5904 100644
--- a/include/persistence_client_custom.h
+++ b/include/persistence_client_custom.h
@@ -1,21 +1,23 @@
 #ifndef PERSISTENCE_CLIENT_LIBRARY_CUSTOM_H
 #define PERSISTENCE_CLIENT_LIBRARY_CUSTOM_H
 
-/****************************************************
- *  persistence_custom.h                                         
- *  Created on: 09-Jul-2012 11:38:03                      
- *  Implementation of the Interface PersCustom       
- *  Original author: ihuerner, G.Sagnes
- *
- *  \file   persistence_client_custom.h
- *  \brief  Implementation of the Interface PersCustom
- *
- *  \par Responsibility
- *   - SW-Subsystem:         EG-SI
- *   - SW-Domain:            Persistence
- *   - Interface Visibility: Protected
- *  \par change history
- *  \verbatim
+/******************************************************************************
+ * Project         Persistency
+ * (c) copyright   2012
+ * Company         XS Embedded GmbH
+ *****************************************************************************/
+/******************************************************************************
+ * This Source Code Form is subject to the terms of the
+ * Mozilla Public License, v. 2.0. If a  copy of the MPL was not distributed
+ * with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
+******************************************************************************/
+ /**
+ * @file           persistence_client_custom.h
+ * @ingroup        Persistence client library
+ * @author         Ingo Huerner (XSe) / Guy Sagnes (Continental)
+ * @brief          Header of the persistence client library custom plugin.
+ *                 Library provides an plugin API to extend persistence client library
+ * @par change history
  *  Date       Author    Version  Description 
  *  2013.06.26 ihuerner  1.5.0.0  added description of parameters
  *  2013.01.06 ihuerner  1.4.0.0  plugin_handle_open and plugin_set_data changed from char* to const char*
@@ -23,9 +25,8 @@
  *  2012.10.16 gsagnes   1.2.0.0  add get_size, create_backup, restore_backup
  *  2012.10.04 gsagnes   1.1.0.0  add deinitialisation functionality (call during shutdown)
  *  2012.07.14 ihuerner  1.0.0.0  Initial version of the interface
- *  \endverbatim
- *
- ****************************************************/
+ */
+
  
 /** \ingroup GEN_PERS_CLIENTLIB_INTERFACE API document
  *  \{
@@ -51,14 +52,14 @@ The lower significant byte is equal 0 for released version only
  *
  * @param backup_id Name of the backup / identifier
  *
- * @return positive value: backup success (size of backup, bytes); negative value: error
+ * @return positive value (0 or greater): backup success (size of backup, bytes); negative value: error
  */
 int plugin_create_backup(const char* backup_id);
 
  /**
  * @brief deinitialize plugin (during shutdown)
  *
- * @return positive value: init success; negative value: error
+ * @return positive value (0 or greater): init success; negative value: error
  */
 int plugin_deinit();
 
@@ -67,7 +68,7 @@ int plugin_deinit();
  *
  * @param path the path to the data to delete
  *
- * @return positive value: delete success; negative value: error
+ * @return positive value (0 or greater): delete success; negative value: error
  */
 int plugin_delete_data(const char* path);
 
@@ -77,7 +78,7 @@ int plugin_delete_data(const char* path);
  * @param backup_id Name of the backup / identifier
  * @param size size of the buffer to return the identifier
  *
- * @return positive value: success, length of identifier; negative value: error
+ * @return positive value (0 or greater): success, length of identifier; negative value: error
  */
 int plugin_get_backup(char* backup_id, int size);
 
@@ -86,7 +87,7 @@ int plugin_get_backup(char* backup_id, int size);
  *
  * @param path the path to the data
  *
- * @return positive value: the size; negative value: error code
+ * @return positive value (0 or greater): the size; negative value: error code
  */
 int plugin_get_size(const char* path);
 
@@ -97,7 +98,7 @@ int plugin_get_size(const char* path);
  * @param buffer the buffer to store data
  * @param size the number of bytes to get data
  *
- * @return positive value: size data read in bytes; negative value: error
+ * @return positive value (0 or greater): size data read in bytes; negative value: error
  */
 int plugin_get_data(const char* path, char* buffer, int size);
  
@@ -106,7 +107,7 @@ int plugin_get_data(const char* path, char* buffer, int size);
  *
  * @param handle the handle to close
  *
- * @return positive value: successfully closed; negative value: error
+ * @return positive value (0 or greater): successfully closed; negative value: error
  */
 int plugin_handle_close(int handle);
 
@@ -117,7 +118,7 @@ int plugin_handle_close(int handle);
  * @param buffer the buffer to store data
  * @param size the number of bytes to get data
  *
- * @return positive value: size data read in bytes; negative value: error
+ * @return positive value (0 or greater): size data read in bytes; negative value: error
  */
 int plugin_handle_get_data(int handle, char* buffer, int size);
 
@@ -128,7 +129,7 @@ int plugin_handle_get_data(int handle, char* buffer, int size);
  * @param flag open flags
  * @param mode the open mode
  *
- * @return positive value: handle; negative value: error
+ * @return positive value (0 or greater): handle; negative value: error
  */
 int plugin_handle_open(const char* path, int flag, int mode);
 
@@ -155,7 +156,7 @@ int plugin_init();
  *
  * @param backup_id Name of the backup / identifier
  *
- * @return positive value: backup success (size of backup, bytes); negative value: error
+ * @return positive value (0 or greater): backup success (size of backup, bytes); negative value: error
  */
 int plugin_restore_backup(const char* backup_id);
 
diff --git a/include/persistence_client_library.h b/include/persistence_client_library.h
index dbddfe8..4370158 100644
--- a/include/persistence_client_library.h
+++ b/include/persistence_client_library.h
@@ -65,8 +65,9 @@ extern "C" {
  * @param shutdownMode shutdown mode ::PCL_SHUTDOWN_TYPE_FAST or ::PCL_SHUTDOWN_TYPE_NORMAL
  *
  * @return positive value: success;
- *   On error a negative value will be returned with th follwoing error codes:
- *   ::EPERS_LOCKFS, ::EPERS_NOT_INITIALIZED, ::EPERS_INIT_DBUS_MAINLOOP,
+ *   On error a negative value will be returned with th following error codes:
+ *   ::EPERS_NOT_INITIALIZED, ::EPERS_INIT_DBUS_MAINLOOP,
+ *   ::EPERS_REGISTER_LIFECYCLE, ::EPERS_REGISTER_ADMIN
  */
 int pclInitLibrary(const char* appname, int shutdownMode);
 
@@ -78,7 +79,7 @@ int pclInitLibrary(const char* appname, int shutdownMode);
  * @attention This function is currently  N O T  part of the GENIVI compliance specification
  *
  * @return positive value: success;
- *   On error a negative value will be returned with th follwoing error codes: ::EPERS_LOCKFS
+ *   On error a negative value will be returned.
  */
 int pclDeinitLibrary(void);
 
diff --git a/include/persistence_client_library_error_def.h b/include/persistence_client_library_error_def.h
index f23c6da..8a4a63f 100644
--- a/include/persistence_client_library_error_def.h
+++ b/include/persistence_client_library_error_def.h
@@ -27,7 +27,7 @@
 extern "C" {
 #endif
 
-// common error, for this error errno will be set
+/// common error, for this error errno will be set
 #define EPERS_COMMON             (-1)
 /// file system is locked
 #define EPERS_LOCKFS             (-2)
@@ -103,7 +103,8 @@ extern "C" {
 #define EPERS_REGISTER_ADMIN     (-36)
 // registration on this key is not allowed
 #define EPERS_NOTIFY_NOT_ALLOWED (-37)
-
+// the requested resource is not a file
+#define EPERS_RESOURCE_NO_FILE   (-38)
 
 #ifdef __cplusplus
 }
diff --git a/include/persistence_client_library_file.h b/include/persistence_client_library_file.h
index 5f26eef..c357714 100644
--- a/include/persistence_client_library_file.h
+++ b/include/persistence_client_library_file.h
@@ -44,8 +44,10 @@ extern "C" {
  *
  * @param fd the file descriptor to close
  *
- * @return zero on success. On error a negative value will be returned with th follwoing error codes:
- *                          ::EPERS_LOCKFS, ::EPERS_MAXHANDLE
+ * @return zero on success.
+ * On error a negative value will be returned with th following error codes:
+ * ::EPERS_MAXHANDLE ::EPERS_COMMON
+ * If ::EPERS_COMMON will be returned errno will be set.
  */
 int pclFileClose(int fd);
 
@@ -56,7 +58,8 @@ int pclFileClose(int fd);
  *
  * @param fd the POSIX file descriptor
  *
- * @return positive value. On error the negative value -1 will be returned
+ * @return positive value (0 or greater). On error ::EPERS_NOT_INITIALIZED, ::EPERS_COMMON
+ * If ::EPERS_COMMON will be returned errno will be set.
  */
 int pclFileGetSize(int fd);
 
@@ -85,9 +88,11 @@ void* pclFileMapData(void* addr, long size, long offset, int fd);
  * @param user_no  the user ID; user_no=0 can not be used as user-ID beacause ‘0’ is defined as System/node
  * @param seat_no  the seat number
  *
- * @return positive value: the POSIX file descriptor;
- * On error a negative value will be returned with th follwoing error codes:
- * EPERS_LOCKFS, EPERS_MAXHANDLE, EPERS_NOKEY, EPERS_NOKEYDATA, EPERS_NOPRCTABLE or EPERS_COMMON,
+ * @return positive value (0 or greater): the POSIX file descriptor;
+ * On error a negative value will be returned with th following error codes:
+ * ::EPERS_LOCKFS, ::EPERS_MAXHANDLE, ::EPERS_NOKEY, ::EPERS_NOKEYDATA,
+ * ::EPERS_NOPRCTABLE, ::EPERS_NOT_INITIALIZED, ::EPERS_COMMON
+ * If ::EPERS_COMMON will be returned errno will be set.
  */
 int pclFileOpen(unsigned int ldbid, const char* resource_id, unsigned int user_no, unsigned int seat_no);
 
@@ -100,9 +105,10 @@ int pclFileOpen(unsigned int ldbid, const char* resource_id, unsigned int user_n
  * @param buffer buffer to read the data
  * @param buffer_size the size buffer for reading
  *
- * @return positive value: the size read;
- * On error a negative value will be returned with th follwoing error codes:
- * EPERS_LOCKFS or EPERS_COMMON
+ * @return positive value (0 or greater): the size read;
+ * On error a negative value will be returned with th following error codes:
+ * ::EPERS_NOT_INITIALIZED, ::EPERS_LOCKFS, ::EPERS_COMMON.
+ * If ::EPERS_COMMON will be returned errno will be set
  */
 int pclFileReadData(int fd, void * buffer, int buffer_size);
 
@@ -116,9 +122,10 @@ int pclFileReadData(int fd, void * buffer, int buffer_size);
  * @param user_no  the user ID; user_no=0 can not be used as user-ID beacause ‘0’ is defined as System/node
  * @param seat_no  the seat number
  *
- * @return positive value: success;
- * On error a negative value will be returned with th follwoing error codes:
- * EPERS_LOCKFS or EPERS_COMMON
+ * @return positive value (0 or greater): success;
+ * On error a negative value will be returned with th following error codes:
+ * ::EPERS_NOT_INITIALIZED, ::EPERS_LOCKFS, ::EPERS_COMMON.
+ * If ::EPERS_COMMON will be returned errno will be set
  */
 int pclFileRemove(unsigned int ldbid, const char* resource_id, unsigned int user_no, unsigned int seat_no);
 
@@ -137,9 +144,10 @@ int pclFileRemove(unsigned int ldbid, const char* resource_id, unsigned int user
                  SEEK_END
                       The offset is set to the size of the file plus offset bytes.
  *
- * @return positive value: resulting offset location;
- * On error a negative value will be returned with th follwoing error codes:
- * EPERS_LOCKFS or EPERS_COMMON
+ * @return positive value (0 or greater): resulting offset location;
+ * On error a negative value will be returned with th following error codes:
+ * ::EPERS_LOCKFS, ::EPERS_NOT_INITIALIZED, ::EPERS_COMMON.
+ * If ::EPERS_COMMON will be returned errno will be set
  */
 int pclFileSeek(int fd, long int offset, int whence);
 
@@ -152,8 +160,9 @@ int pclFileSeek(int fd, long int offset, int whence);
  * @param size the size in bytes to unmap
  *
  * @return on success 0;
- * On error a negative value will be returned with th follwoing error codes:
- * EPERS_LOCKFS or EPERS_COMMON
+ * On error a negative value will be returned with th following error codes:
+ * ::EPERS_LOCKFS, EPERS_NOT_INITIALIZED, ::EPERS_COMMON.
+ * If ::EPERS_COMMON will be returned errno will be set
  */
 int pclFileUnmapData(void* address, long size);
 
@@ -166,9 +175,10 @@ int pclFileUnmapData(void* address, long size);
  * @param buffer the buffer to write
  * @param buffer_size the size of the buffer to write in bytes
  *
- * @return positive value: bytes written;
- * On error a negative value will be returned with th follwoing error codes:
- * EPERS_LOCKFS or EPERS_COMMON
+ * @return positive value (0 or greater): bytes written;
+ * On error a negative value will be returned with th following error codes:
+ * ::EPERS_LOCKFS, ::EPERS_NOT_INITIALIZED or ::EPERS_COMMON
+ * If ::EPERS_COMMON will be returned errno will be set.
  */
 int pclFileWriteData(int fd, const void * buffer, int buffer_size);
 
@@ -186,9 +196,10 @@ int pclFileWriteData(int fd, const void * buffer, int buffer_size);
  *
  * @note the allocated memory for the path string will be freed in pclFileReleasePath
  *
- * @return positive value on success, which must be used when pclFileReleasePath will be called
- * On error a negative value will be returned with th follwoing error codes:
- * EPERS_LOCKFS or EPERS_COMMON
+ * @return positive value (0 or greater) on success, which must be used when pclFileReleasePath will be called
+ * On error a negative value will be returned with th following error codes:
+ * ::EPERS_LOCKFS or ::EPERS_COMMON
+ * If ::EPERS_COMMON will be returned errno will be set.
  */
 int pclFileCreatePath(unsigned int ldbid, const char* resource_id, unsigned int user_no, unsigned int seat_no, char** path, unsigned int* size);
 
@@ -200,9 +211,10 @@ int pclFileCreatePath(unsigned int ldbid, const char* resource_id, unsigned int
  *
  * @note the allocated memory in pclFileCreatePath for the path will freed in the function
  *
- * @return positive value: success;
- * On error a negative value will be returned with th follwoing error codes:
- * EPERS_LOCKFS or EPERS_COMMON
+ * @return positive value (0 or greater): success;
+ * On error a negative value will be returned with th following error codes:
+ * ::EPERS_LOCKFS or ::EPERS_COMMON
+ * If ::EPERS_COMMON will be returned errno will be set.
  */
 int pclFileReleasePath(int pathPandle);
 
diff --git a/include/persistence_client_library_key.h b/include/persistence_client_library_key.h
index facad06..fa9fa16 100644
--- a/include/persistence_client_library_key.h
+++ b/include/persistence_client_library_key.h
@@ -85,8 +85,8 @@ typedef struct _pclNotification_s
  *
  * @param notifyStruct structure for notifcation
  *
- * @return positive value: success;
- *   On error a negative value will be returned with the following error codes: ::EPERS_LOCKFS
+ * @return positive value (0 or greater): success;
+ * On error a negative value will be returned with the following error codes: ::EPERS_LOCKFS
 */
 typedef int(* pclChangeNotifyCallback_t)(pclNotification_s * notifyStruct);
 
@@ -103,8 +103,9 @@ typedef int(* pclChangeNotifyCallback_t)(pclNotification_s * notifyStruct);
  * @param user_no  the user ID; user_no=0 can not be used as user-ID beacause ‘0’ is defined as System/node
  * @param seat_no  the seat number
  *
- * @return positive value: success; On error a negative value will be returned with the following error codes:
- * ::EPERS_LOCKFS ::EPERS_NOTIFY_SIG
+ * @return positive value (0 or greater) : success;
+ * On error a negative value will be returned with the following error codes:
+ * ::EPERS_LOCKFS, ::EPERS_NOTIFY_SIG, ::EPERS_NOT_INITIALIZED, ::EPERS_BADPOL
  */
 int pclKeyDelete(unsigned int ldbid, const char* resource_id, unsigned int user_no, unsigned int seat_no);
 
@@ -118,8 +119,10 @@ int pclKeyDelete(unsigned int ldbid, const char* resource_id, unsigned int user_
  * @param user_no  the user ID; user_no=0 can not be used as user-ID beacause ‘0’ is defined as System/node
  * @param seat_no  the seat number
  *
- * @return positive value: the size; On error a negative value will be returned with the following error codes:
+ * @return positive value (0 or greater): the size;
+ * On error a negative value will be returned with the following error codes:
  * ::EPERS_LOCKFS, ::EPERS_BADPOL, ::EPERS_NOKEY, ::EPERS_NOKEYDATA or ::EPERS_NOPRCTABLE
+ * ::EPERS_NOT_INITIALIZED
  */
 int pclKeyGetSize(unsigned int ldbid, const char* resource_id, unsigned int user_no, unsigned int seat_no);
 
@@ -128,8 +131,9 @@ int pclKeyGetSize(unsigned int ldbid, const char* resource_id, unsigned int user
  *
  * @param key_handle key value handle return by key_handle_open()
  *
- * @return positive value: success; On error a negative value will be returned with the following error codes:
- * ::EPERS_LOCKFS
+ * @return positive value (0 or greater): success;
+ * On error a negative value will be returned with the following error codes:
+ * ::EPERS_LOCKFS ::EPERS_MAXHANDLE ::EPERS_NOPLUGINFUNCT ::EPERS_NOT_INITIALIZED
  */
 int pclKeyHandleClose(int key_handle);
 
@@ -140,8 +144,10 @@ int pclKeyHandleClose(int key_handle);
  *
  * @param key_handle key value handle return by key_handle_open()
  *
- * @return positive value: the size; On error a negative value will be returned with the following error codes:
- * ::EPERS_LOCKFS
+ * @return positive value (0 or greater): the size;
+ * On error a negative value will be returned with the following error codes:
+ * ::EPERS_NOT_INITIALIZED ::EPERS_LOCKFS ::EPERS_NOPLUGINFUNCT ::EPERS_MAXHANDLE
+ * ::EPERS_NOKEY ::EPERS_DB_KEY_SIZE ::EPERS_NOPRCTABLE
  */
 int pclKeyHandleGetSize(int key_handle);
 
@@ -155,9 +161,9 @@ int pclKeyHandleGetSize(int key_handle);
  * @param user_no  the user ID; user_no=0 can not be used as user-ID beacause ‘0’ is defined as System/node
  * @param seat_no  the seat number
  *
- * @return positive value: the key handle to access the value;
+ * @return positive value (0 or greater): the key handle to access the value;
  * On error a negative value will be returned with the following error codes:
- * ::EPERS_LOCKFS
+ * ::EPERS_NOT_INITIALIZED ::EPERS_NOPLUGINFUNCT ::
  */
 int pclKeyHandleOpen(unsigned int ldbid, const char* resource_id, unsigned int user_no, unsigned int seat_no);
 
@@ -170,8 +176,9 @@ int pclKeyHandleOpen(unsigned int ldbid, const char* resource_id, unsigned int u
  * @param buffer the buffer for persistent data
  * @param buffer_size size of buffer for reading
  *
- * @return positive value: the bytes read; On error a negative value will be returned with the following error codes:
- * ::EPERS_LOCKFS
+ * @return positive value (0 or greater): the bytes read;
+ * On error a negative value will be returned with the following error codes:
+ * ::EPERS_NOT_INITIALIZED ::EPERS_NOPLUGINFUNCT ::EPERS_MAXHANDLE
  */
 int pclKeyHandleReadData(int key_handle, unsigned char* buffer, int buffer_size);
 
@@ -183,22 +190,28 @@ int pclKeyHandleReadData(int key_handle, unsigned char* buffer, int buffer_size)
  * @param key_handle key value handle return by key_handle_open()
  * @param callback notification callback
  *
- * @return positive value: registration OK; On error a negative value will be returned with the following error codes:
- * ::EPERS_LOCKFS ::EPERS_MAXHANDLE ::EPERS_NOTIFY_NOT_ALLOWED
+ * @return positive value (0 or greater): registration OK;
+ * On error a negative value will be returned with the following error codes:
+ * ::EPERS_NOT_INITIALIZED ::EPERS_MAXHANDLE ::EPERS_NOTIFY_NOT_ALLOWED
  */
 int pclKeyHandleRegisterNotifyOnChange(int key_handle, pclChangeNotifyCallback_t callback);
 
+
+
 /**
  * @brief unregister a change notification for persistent data
  *
  * @param key_handle key value handle return by key_handle_open()
  * @param callback notification callback
  *
- * @return positive value: registration OK; On error a negative value will be returned with the following error codes:
- * ::EPERS_LOCKFS ::EPERS_MAXHANDLE ::EPERS_NOTIFY_NOT_ALLOWED
+ * @return positive value (0 or greater): registration OK;
+ * On error a negative value will be returned with the following error codes:
+ * ::EPERS_NOT_INITIALIZED ::EPERS_LOCKFS ::EPERS_MAXHANDLE ::EPERS_NOTIFY_NOT_ALLOWED
  */
 int pclKeyHandleUnRegisterNotifyOnChange(int key_handle, pclChangeNotifyCallback_t callback);
 
+
+
 /**
  * @brief writes persistent data identified by key handle
  *
@@ -207,8 +220,10 @@ int pclKeyHandleUnRegisterNotifyOnChange(int key_handle, pclChangeNotifyCallback
  * @param buffer_size the number of bytes to write (default max size is set to 16kB)
  *                    use environment variable PERS_MAX_KEY_VAL_DATA_SIZE to modify default size in bytes
  *
- * @return positive value: the bytes written; On error a negative value will be returned with the following error codes:
- * ::EPERS_LOCKFS ::EPERS_MAX_BUFF_SIZE ::EPERS_NOTIFY_SIG
+ * @return positive value (0 or greater): the bytes written;
+ * On error a negative value will be returned with the following error codes:
+ * ::EPERS_LOCKFS ::EPERS_MAX_BUFF_SIZE ::EPERS_NOTIFY_SIG ::EPERS_DB_VALUE_SIZE ::EPERS_DB_KEY_SIZE
+ * ::EPERS_NOPRCTABLE ::EPERS_DB_VALUE_SIZE
  */
 int pclKeyHandleWriteData(int key_handle, unsigned char* buffer, int buffer_size);
 
@@ -224,8 +239,9 @@ int pclKeyHandleWriteData(int key_handle, unsigned char* buffer, int buffer_size
  * @param buffer the buffer to read the persistent data
  * @param buffer_size size of buffer for reading
  *
- * @return positive value: the bytes read; On error a negative value will be returned with th follwoing error codes:
- * ::EPERS_LOCKFS
+ * @return positive value (0 or greater): the bytes read;
+ * On error a negative value will be returned with th following error codes:
+ * ::EPERS_LOCKFS ::EPERS_NOT_INITIALIZED ::EPERS_BADPOL ::EPERS_NOPLUGINFUNCT
  */
 int pclKeyReadData(unsigned int ldbid, const char* resource_id, unsigned int user_no, unsigned int seat_no, unsigned char* buffer, int buffer_size);
 
@@ -240,8 +256,9 @@ int pclKeyReadData(unsigned int ldbid, const char* resource_id, unsigned int use
  * @param seat_no  the seat number
  * @param callback notification callback
  *
- * @return positive value: registration OK; On error a negative value will be returned with the following error codes:
- *                         ::EPERS_RES_NO_KEY ::EPERS_NOKEYDATA  ::EPERS_NOPRCTABLE ::EPERS_NOTIFY_NOT_ALLOWED
+ * @return positive value (0 or greater): registration OK;
+ * On error a negative value will be returned with the following error codes:
+ * ::EPERS_RES_NO_KEY ::EPERS_NOKEYDATA  ::EPERS_NOPRCTABLE ::EPERS_NOTIFY_NOT_ALLOWED
  */
 int pclKeyRegisterNotifyOnChange(unsigned int ldbid, const char* resource_id, unsigned int user_no, unsigned int seat_no, pclChangeNotifyCallback_t callback);
 
@@ -256,11 +273,14 @@ int pclKeyRegisterNotifyOnChange(unsigned int ldbid, const char* resource_id, un
  * @param seat_no  the seat number
  * @param callback notification callback
  *
- * @return positive value: registration OK; On error a negative value will be returned with the following error codes:
- *                         ::EPERS_RES_NO_KEY ::EPERS_NOKEYDATA  ::EPERS_NOPRCTABLE ::EPERS_NOTIFY_NOT_ALLOWED
+ * @return positive value (0 or greater): registration OK;
+ * On error a negative value will be returned with the following error codes:
+ * ::EPERS_RES_NO_KEY ::EPERS_NOKEYDATA  ::EPERS_NOPRCTABLE ::EPERS_NOTIFY_NOT_ALLOWED
  */
 int pclKeyUnRegisterNotifyOnChange( unsigned int  ldbid, const char *  resource_id, unsigned int  user_no, unsigned int  seat_no, pclChangeNotifyCallback_t  callback);
 
+
+
 /**
  * @brief writes persistent data identified by ldbid and resource_id
  *
@@ -272,11 +292,13 @@ int pclKeyUnRegisterNotifyOnChange( unsigned int  ldbid, const char *  resource_
  * @param buffer_size the number of bytes to write (default max size is set to 16kB)
  *                    use environment variable PERS_MAX_KEY_VAL_DATA_SIZE to modify default size in bytes
  *
- * @return positive value: the bytes written; On error a negative value will be returned with the following error codes:
- * ::EPERS_LOCKFS ::EPERS_NOTIFY_NOT_ALLOWED
+ * @return positive value (0 or greater): the bytes written;
+ * On error a negative value will be returned with the following error codes:
+ * ::EPERS_LOCKFS ::EPERS_BADPOL ::EPERS_BUFLIMIT ::EPERS_DB_VALUE_SIZE ::EPERS_DB_KEY_SIZE ::EPERS_NOTIFY_SIG
  */
 int pclKeyWriteData(unsigned int ldbid, const char* resource_id, unsigned int user_no, unsigned int seat_no, unsigned char* buffer, int buffer_size);
 
+
 /** \} */
 
 #ifdef __cplusplus