diff -r 865c84fef6b4 -r 4384fe041d6e src/cx/buffer.h
--- a/src/cx/buffer.h	Sat Jan 04 14:19:11 2025 +0100
+++ b/src/cx/buffer.h	Sat Jan 04 15:41:02 2025 +0100
@@ -27,9 +27,9 @@
  */
 
 /**
- * \file buffer.h
+ * @file buffer.h
  *
- * \brief Advanced buffer implementation.
+ * @brief Advanced buffer implementation.
  *
  * Instances of CxBuffer can be used to read from or to write to like one
  * would do with a stream.
@@ -38,9 +38,9 @@
  * can be enabled. See the documentation of the macro constants for more
  * information.
  *
- * \author Mike Becker
- * \author Olaf Wintermann
- * \copyright 2-Clause BSD License
+ * @author Mike Becker
+ * @author Olaf Wintermann
+ * @copyright 2-Clause BSD License
  */
 
 #ifndef UCX_BUFFER_H
@@ -89,7 +89,7 @@
 #define CX_BUFFER_COPY_ON_EXTEND 0x08
 
 /** Structure for the UCX buffer data. */
-typedef struct {
+struct cx_buffer_s {
     /** A pointer to the buffer contents. */
     union {
         /**
@@ -111,7 +111,7 @@
     size_t size;
     /**
      * The buffer may not extend beyond this threshold before starting to flush.
-     * Default is \c SIZE_MAX (flushing disabled when auto extension is enabled).
+     * Default is @c SIZE_MAX (flushing disabled when auto extension is enabled).
      */
     size_t flush_threshold;
     /**
@@ -122,13 +122,13 @@
     /**
      * The maximum number of blocks to flush in one cycle.
      * Zero disables flushing entirely (this is the default).
-     * Set this to \c SIZE_MAX to flush the entire buffer.
+     * Set this to @c SIZE_MAX to flush the entire buffer.
      *
      * @attention if the maximum number of blocks multiplied with the block size
      * is smaller than the expected contents written to this buffer within one write
      * operation, multiple flush cycles are performed after that write.
      * That means the total number of blocks flushed after one write to this buffer may
-     * be larger than \c flush_blkmax.
+     * be larger than @c flush_blkmax.
      */
     size_t flush_blkmax;
 
@@ -139,7 +139,7 @@
     cx_write_func flush_func;
 
     /**
-     * The target for \c flush_func.
+     * The target for @c flush_func.
      */
     void *flush_target;
 
@@ -151,41 +151,41 @@
      * @see #CX_BUFFER_COPY_ON_WRITE
      */
     int flags;
-} cx_buffer_s;
+};
 
 /**
  * UCX buffer.
  */
-typedef cx_buffer_s CxBuffer;
+typedef struct cx_buffer_s CxBuffer;
 
 /**
  * Initializes a fresh buffer.
  *
- * You may also provide a read-only \p space, in which case
+ * You may also provide a read-only @p space, in which case
  * you will need to cast the pointer, and you should set the
  * #CX_BUFFER_COPY_ON_WRITE flag.
  *
  * You need to set the size manually after initialization, if
- * you provide \p space which already contains data.
+ * you provide @p space which already contains data.
  *
- * When you specify stack memory as \p space and decide to use
- * the auto-extension feature, you \em must use the
+ * When you specify stack memory as @p space and decide to use
+ * the auto-extension feature, you @em must use the
  * #CX_BUFFER_COPY_ON_EXTEND flag, instead of the
  * #CX_BUFFER_AUTO_EXTEND flag.
  *
- * \note You may provide \c NULL as argument for \p space.
+ * @note You may provide @c NULL as argument for @p space.
  * Then this function will allocate the space and enforce
  * the #CX_BUFFER_FREE_CONTENTS flag. In that case, specifying
  * copy-on-write should be avoided, because the allocated
  * space will be leaking after the copy-on-write operation.
  *
  * @param buffer the buffer to initialize
- * @param space pointer to the memory area, or \c NULL to allocate
+ * @param space pointer to the memory area, or @c NULL to allocate
  * new memory
  * @param capacity the capacity of the buffer
  * @param allocator the allocator this buffer shall use for automatic
  * memory management
- * (if \c NULL, a default stdlib allocator will be used)
+ * (if @c NULL, a default stdlib allocator will be used)
  * @param flags buffer features (see cx_buffer_s.flags)
  * @return zero on success, non-zero if a required allocation failed
  */
@@ -214,9 +214,9 @@
  * Deallocates the buffer.
  *
  * If the #CX_BUFFER_FREE_CONTENTS feature is enabled, this function also destroys
- * the contents. If you \em only want to destroy the contents, use cxBufferDestroy().
+ * the contents. If you @em only want to destroy the contents, use cxBufferDestroy().
  *
- * \remark As with all free() functions, this accepts \c NULL arguments in which
+ * @remark As with all free() functions, this accepts @c NULL arguments in which
  * case it does nothing.
  *
  * @param buffer the buffer to deallocate
@@ -227,26 +227,26 @@
 /**
  * Allocates and initializes a fresh buffer.
  *
- * You may also provide a read-only \p space, in which case
+ * You may also provide a read-only @p space, in which case
  * you will need to cast the pointer, and you should set the
  * #CX_BUFFER_COPY_ON_WRITE flag.
- * When you specify stack memory as \p space and decide to use
- * the auto-extension feature, you \em must use the
+ * When you specify stack memory as @p space and decide to use
+ * the auto-extension feature, you @em must use the
  * #CX_BUFFER_COPY_ON_EXTEND flag, instead of the
  * #CX_BUFFER_AUTO_EXTEND flag.
  *
- * \note You may provide \c NULL as argument for \p space.
+ * @note You may provide @c NULL as argument for @p space.
  * Then this function will allocate the space and enforce
  * the #CX_BUFFER_FREE_CONTENTS flag.
  *
- * @param space pointer to the memory area, or \c NULL to allocate
+ * @param space pointer to the memory area, or @c NULL to allocate
  * new memory
  * @param capacity the capacity of the buffer
  * @param allocator the allocator to use for allocating the structure and the automatic
  * memory management within the buffer
- * (if \c NULL, a default stdlib allocator will be used)
+ * (if @c NULL, a default stdlib allocator will be used)
  * @param flags buffer features (see cx_buffer_s.flags)
- * @return a pointer to the buffer on success, \c NULL if a required allocation failed
+ * @return a pointer to the buffer on success, @c NULL if a required allocation failed
  */
 cx_attr_malloc
 cx_attr_dealloc(cxBufferFree, 1)
@@ -269,7 +269,7 @@
  * are discarded.
  *
  * If the offset is negative, the contents are shifted to the left where the
- * first \p shift bytes are discarded.
+ * first @p shift bytes are discarded.
  * The new size of the buffer is the old size minus the absolute shift value.
  * If this value is larger than the buffer size, the buffer is emptied (but
  * not cleared, see the security note below).
@@ -277,11 +277,11 @@
  * The buffer position gets shifted alongside with the content but is kept
  * within the boundaries of the buffer.
  *
- * \note For situations where \c off_t is not large enough, there are specialized cxBufferShiftLeft() and
- * cxBufferShiftRight() functions using a \c size_t as parameter type.
+ * @note For situations where @c off_t is not large enough, there are specialized cxBufferShiftLeft() and
+ * cxBufferShiftRight() functions using a @c size_t as parameter type.
  *
- * \attention
- * Security Note: The shifting operation does \em not erase the previously occupied memory cells.
+ * @attention
+ * Security Note: The shifting operation does @em not erase the previously occupied memory cells.
  * But you can easily do that manually, e.g. by calling
  * <code>memset(buffer->bytes, 0, shift)</code> for a right shift or
  * <code>memset(buffer->bytes + buffer->size, 0, buffer->capacity - buffer->size)</code>
@@ -289,7 +289,10 @@
  *
  * @param buffer the buffer
  * @param shift the shift offset (negative means left shift)
- * @return 0 on success, non-zero if a required auto-extension or copy-on-write fails
+ * @retval zero success
+ * @retval non-zero if a required auto-extension or copy-on-write fails
+ * @see cxBufferShiftLeft()
+ * @see cxBufferShiftRight()
  */
 cx_attr_nonnull
 int cxBufferShift(
@@ -303,7 +306,8 @@
  *
  * @param buffer the buffer
  * @param shift the shift offset
- * @return 0 on success, non-zero if a required auto-extension or copy-on-write fails
+ * @retval zero success
+ * @retval non-zero if a required auto-extension or copy-on-write fails
  * @see cxBufferShift()
  */
 cx_attr_nonnull
@@ -318,7 +322,8 @@
  *
  * @param buffer the buffer
  * @param shift the positive shift offset
- * @return usually zero, except the buffer uses copy-on-write and the allocation fails
+ * @retval zero success
+ * @retval non-zero if the buffer uses copy-on-write and the allocation fails
  * @see cxBufferShift()
  */
 cx_attr_nonnull
@@ -331,20 +336,21 @@
 /**
  * Moves the position of the buffer.
  *
- * The new position is relative to the \p whence argument.
+ * The new position is relative to the @p whence argument.
  *
- * \li \c SEEK_SET marks the start of the buffer.
- * \li \c SEEK_CUR marks the current position.
- * \li \c SEEK_END marks the end of the buffer.
+ * @li @c SEEK_SET marks the start of the buffer.
+ * @li @c SEEK_CUR marks the current position.
+ * @li @c SEEK_END marks the end of the buffer.
  *
  * With an offset of zero, this function sets the buffer position to zero
- * (\c SEEK_SET), the buffer size (\c SEEK_END) or leaves the buffer position
- * unchanged (\c SEEK_CUR).
+ * (@c SEEK_SET), the buffer size (@c SEEK_END) or leaves the buffer position
+ * unchanged (@c SEEK_CUR).
  *
  * @param buffer the buffer
- * @param offset position offset relative to \p whence
- * @param whence one of \c SEEK_SET, \c SEEK_CUR or \c SEEK_END
- * @return 0 on success, non-zero if the position is invalid
+ * @param offset position offset relative to @p whence
+ * @param whence one of @c SEEK_SET, @c SEEK_CUR or @c SEEK_END
+ * @retval zero success
+ * @retval non-zero if the position is invalid
  *
  */
 cx_attr_nonnull
@@ -360,7 +366,7 @@
  * The data is deleted by zeroing it with a call to memset().
  * If you do not need that, you can use the faster cxBufferReset().
  *
- * \note If the #CX_BUFFER_COPY_ON_WRITE flag is set, this function
+ * @note If the #CX_BUFFER_COPY_ON_WRITE flag is set, this function
  * will not erase the data and behave exactly as cxBufferReset().
  *
  * @param buffer the buffer to be cleared
@@ -385,8 +391,9 @@
  * Tests, if the buffer position has exceeded the buffer size.
  *
  * @param buffer the buffer to test
- * @return true, if the current buffer position has exceeded the last
- * byte of the buffer's contents.
+ * @retval true if the current buffer position has exceeded the last
+ * byte of the buffer's contents
+ * @retval false otherwise
  */
 cx_attr_nonnull
 cx_attr_nodiscard
@@ -400,7 +407,8 @@
  *
  * @param buffer the buffer
  * @param capacity the minimum required capacity for this buffer
- * @return 0 on success or a non-zero value on failure
+ * @retval zero the capacity was already sufficient or successfully increased
+ * @retval non-zero on allocation failure
  */
 cx_attr_nonnull
 int cxBufferMinimumCapacity(
@@ -420,19 +428,24 @@
  * buffer are both incapable of taking more data or all data has been written.
  * The number returned by this function is the total number of elements that
  * could be written during the process. It does not necessarily mean that those
- * elements are still in this buffer, because some of them could have also be
+ * elements are still in this buffer, because some of them could have also been
  * flushed already.
  *
- * If automatic flushing is not enabled, the position of the buffer is increased
+ * If automatic flushing is not enabled, the data is simply written into the
+ * buffer at the current position and the position of the buffer is increased
  * by the number of bytes written.
+ * Use cxBufferAppend() if you want to add data to this buffer regardless of
+ * the position.
  *
- * \note The signature is compatible with the fwrite() family of functions.
+ * @note The signature is compatible with the fwrite() family of functions.
  *
  * @param ptr a pointer to the memory area containing the bytes to be written
  * @param size the length of one element
  * @param nitems the element count
  * @param buffer the CxBuffer to write to
  * @return the total count of elements written
+ * @see cxBufferAppend()
+ * @see cxBufferRead()
  */
 cx_attr_nonnull
 size_t cxBufferWrite(
@@ -451,7 +464,7 @@
  * while additional data is added to the buffer occasionally.
  * Consequently, the position of the buffer is unchanged after this operation.
  *
- * \note The signature is compatible with the fwrite() family of functions.
+ * @note The signature is compatible with the fwrite() family of functions.
  *
  * @param ptr a pointer to the memory area containing the bytes to be written
  * @param size the length of one element
@@ -459,6 +472,7 @@
  * @param buffer the CxBuffer to write to
  * @return the total count of elements written
  * @see cxBufferWrite()
+ * @see cxBufferRead()
  */
 cx_attr_nonnull
 size_t cxBufferAppend(
@@ -473,13 +487,15 @@
  *
  * The position of the buffer is increased by the number of bytes read.
  *
- * \note The signature is compatible with the fread() family of functions.
+ * @note The signature is compatible with the fread() family of functions.
  *
  * @param ptr a pointer to the memory area where to store the read data
  * @param size the length of one element
  * @param nitems the element count
  * @param buffer the CxBuffer to read from
  * @return the total number of elements read
+ * @see cxBufferWrite()
+ * @see cxBufferAppend()
  */
 cx_attr_nonnull
 size_t cxBufferRead(
@@ -495,14 +511,18 @@
  * The least significant byte of the argument is written to the buffer. If the
  * end of the buffer is reached and #CX_BUFFER_AUTO_EXTEND feature is enabled,
  * the buffer capacity is extended by cxBufferMinimumCapacity(). If the feature
- * is disabled or buffer extension fails, \c EOF is returned.
+ * is disabled or buffer extension fails, @c EOF is returned.
  *
  * On successful write, the position of the buffer is increased.
  *
+ * If you just want to write a null-terminator at the current position, you
+ * should use cxBufferTerminate() instead.
+ *
  * @param buffer the buffer to write to
  * @param c the character to write
- * @return the byte that has been written or \c EOF when the end of the stream is
+ * @return the byte that has been written or @c EOF when the end of the stream is
  * reached and automatic extension is not enabled or not possible
+ * @see cxBufferTerminate()
  */
 cx_attr_nonnull
 int cxBufferPut(
@@ -511,9 +531,9 @@
 );
 
 /**
- * Writes a terminating zero to a buffer.
+ * Writes a terminating zero to a buffer at the current position.
  *
- * On successful write, \em neither the position \em nor the size of the buffer is
+ * On successful write, @em neither the position @em nor the size of the buffer is
  * increased.
  *
  * The purpose of this function is to have the written data ready to be used as
@@ -528,6 +548,8 @@
 /**
  * Writes a string to a buffer.
  *
+ * This is a convenience function for <code>cxBufferWrite(str, 1, strlen(str), buffer)</code>.
+ *
  * @param buffer the buffer
  * @param str the zero-terminated string
  * @return the number of bytes written
@@ -545,7 +567,7 @@
  * The current position of the buffer is increased after a successful read.
  *
  * @param buffer the buffer to read from
- * @return the character or \c EOF, if the end of the buffer is reached
+ * @return the character or @c EOF, if the end of the buffer is reached
  */
 cx_attr_nonnull
 int cxBufferGet(CxBuffer *buffer);