posix: Fixed header comment of aio_read.c

Corrected the header comment of aio_read.c

Fixes #5015

cpukit/posix/src/aio_read.c

@@ -3,9 +3,8 @@
 /**
  * @file
  * 
- * @ingroup POSIXAPI
- *
  * @brief Asynchronously reads Data from a File
+ * @ingroup POSIX_AIO
  */
 
 /*
@@ -46,25 +45,24 @@
 #include <stdlib.h>
 #include <limits.h>
 
-/*
- *  aio_read
- *
- * Asynchronous write to a file
- *
- *  Input parameters:
- *        aiocbp - asynchronous I/O control block
- *
- *  Output parameters:
- *        -1 - request could not pe enqueued
- *           - FD not opened for write
- *           - invalid aio_reqprio or aio_offset or
- *             aio_nbytes
- *           - not enough memory
- *         0 - otherwise
- */
 
-int
-aio_read (struct aiocb *aiocbp)
+ /**
+ * @brief Asynchronous read from a file
+ * 
+ * 6.7.2 Asynchronous Read, P1003.1b-1993, p. 154
+ * 
+ * @param[in] aiocbp is a pointer to the asynchronous I/O control block
+ * 
+ * @retval 0 The request has been successfuly enqueued.
+ * @retval -1 The request has not been enqueued. The possible errors are:
+ *         - FD not opened for read
+ *         - invalid aio_reqprio or aio_offset or aio_nbytes
+ *         - not enough memory
+ *         - the starting position of the file is past the maximum offset
+ *           for this file. 
+ *
+ */
+int aio_read(struct aiocb *aiocbp)
 {
   rtems_aio_request *req;
   int mode;