Changes between Version 17 and Version 18 of file_system

Timestamp:

Jul 8, 2015, 5:45:50 PM (9 years ago)

Author:

alain

Comment:

--

file_system

@@ -119 +119 @@
 
 === int '''_fat_read'''( unsigned int fd_id , void* buffer , unsigned int count ) ===
-This function implements the "giet_fat_read()" system call, that has the same semantic as the UNIX "read()" function.
+This function implements the "giet_fat_read()" system call.
 It access the File-Cache  associated to the file identified by the file descriptor, and transfers "count" bytes from the cache to the user buffer, starting from the current file offset.
 In case of miss in the File_Cache, it loads all involved clusters into the cache.
@@ -125 +125 @@
  * '''buffer''' : pointer on the memory buffer
  * '''count''' : number of bytes 
-It returns the number of bytes actually transfered if success / It returns 0 if (offset + count > file_size) / It returns -1 if failure.
+It returns the number of bytes actually transfered if success. It returns 0 if (offset + count > file_size). It returns a negative value if error:
+ *  -1  : "FAT not initialised"
+ *  -2  : "Illegal file descriptor"
+ *  -3  : "File not open"
+ *  -4  : "Cannot load
 
 === int '''_fat_write'''( unsigned int fd_id , void* buffer , unsigned int count ) ===