diff --git a/library/stdio_fputs.c b/library/stdio_fputs.c
index d1ae641..0668685 100644
--- a/library/stdio_fputs.c
+++ b/library/stdio_fputs.c
@@ -1,10 +1,8 @@
 /*
- * $Id: stdio_fputs.c,v 1.7 2006-01-08 12:04:24 obarthel Exp $
- *
  * :ts=4
  *
  * Portable ISO 'C' (1994) runtime library for the Amiga computer
- * Copyright (c) 2002-2015 by Olaf Barthel <obarthel (at) gmx.net>
+ * Copyright (c) 2002-2019 by Olaf Barthel <obarthel (at) gmx.net>
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -47,8 +45,8 @@ int
 fputs(const char *s, FILE *stream)
 {
 	struct iob * file = (struct iob *)stream;
+	size_t total_size;
 	int result = EOF;
-	int buffer_mode;
 	int c;
 
 	ENTER();
@@ -77,17 +75,162 @@ fputs(const char *s, FILE *stream)
 	assert( FLAG_IS_SET(file->iob_Flags,IOBF_IN_USE) );
 	assert( file->iob_BufferSize > 0 );
 
-	buffer_mode = (file->iob_Flags & IOBF_BUFFER_MODE);
-	if(buffer_mode == IOBF_BUFFER_MODE_NONE)
-		buffer_mode = IOBF_BUFFER_MODE_LINE;
-
 	if(__fputc_check(stream) < 0)
 		goto out;
 
-	while((c = (*s++)) != '\0')
+	total_size = strlen(s);
+	if(total_size > 0)
 	{
-		if(__putc(c,stream,buffer_mode) == EOF)
-			goto out;
+		int buffer_mode;
+
+		/* We perform line buffering to improve readability of the
+		   buffered text if buffering was disabled and the output
+		   goes to an interactive stream. */
+		buffer_mode = (file->iob_Flags & IOBF_BUFFER_MODE);
+		if(buffer_mode == IOBF_BUFFER_MODE_NONE)
+		{
+			struct fd * fd = __fd[file->iob_Descriptor];
+
+			__fd_lock(fd);
+
+			if(FLAG_IS_SET(fd->fd_Flags,FDF_IS_INTERACTIVE))
+				buffer_mode = IOBF_BUFFER_MODE_LINE;
+
+			__fd_unlock(fd);
+		}
+
+		if (buffer_mode == IOBF_BUFFER_MODE_LINE)
+		{
+			while(total_size > 0)
+			{
+				/* Is there still room in the write buffer to store
+				   more of the string? */
+				if(file->iob_BufferWriteBytes < file->iob_BufferSize)
+				{
+					unsigned char * buffer = &file->iob_Buffer[file->iob_BufferWriteBytes];
+					size_t num_buffer_bytes;
+					const char * lf;
+
+					/* Store only as many characters as will fit into the write buffer. */
+					num_buffer_bytes = file->iob_BufferSize - file->iob_BufferWriteBytes;
+					if(total_size < num_buffer_bytes)
+						num_buffer_bytes = total_size;
+
+					/* Try to find a line feed in the string. If there is one,
+					   reduce the number of characters to write to the sequence
+					   which ends with the line feed character. */
+					lf = memchr(s, '\n', num_buffer_bytes);
+					if(lf != NULL)
+						num_buffer_bytes = lf + 1 - s;
+
+					memmove(buffer, s, num_buffer_bytes);
+					s += num_buffer_bytes;
+
+					file->iob_BufferWriteBytes += num_buffer_bytes;
+
+					/* Write the buffer to disk if it's full or contains a line feed. */
+					if((lf != NULL || __iob_write_buffer_is_full(file)) && __flush_iob_write_buffer(file) < 0)
+					{
+						/* Abort with error. */
+						goto out;
+					}
+
+					/* Stop as soon as no further data needs to be written. */
+					total_size -= num_buffer_bytes;
+					if(total_size == 0)
+						break;
+
+					/* If there is again room in the output buffer,
+					   repeat this optimization. */
+					if(file->iob_BufferWriteBytes < file->iob_BufferSize)
+						continue;
+				}
+
+				c = (*s++);
+
+				if(__putc_line_buffered(c,(FILE *)file) == EOF)
+					goto out;
+
+				total_size--;
+			}
+		}
+		else if (buffer_mode == IOBF_BUFFER_MODE_NONE)
+		{
+			ssize_t num_bytes_written;
+
+			/* We bypass the buffer entirely. */
+			num_bytes_written = write(file->iob_Descriptor, s, total_size);
+			if(num_bytes_written == -1)
+			{
+				SET_FLAG(file->iob_Flags,IOBF_ERROR);
+				goto out;
+			}
+		}
+		else
+		{
+			while(total_size > 0)
+			{
+				/* If there is more data to be written than the write buffer will hold
+				   and the write buffer is empty anyway, then we'll bypass the write
+				   buffer entirely. */
+				if(file->iob_BufferWriteBytes == 0 && total_size >= (size_t)file->iob_BufferSize)
+				{
+					ssize_t num_bytes_written;
+
+					/* We bypass the buffer entirely. */
+					num_bytes_written = write(file->iob_Descriptor, s, total_size);
+					if(num_bytes_written == -1)
+					{
+						SET_FLAG(file->iob_Flags,IOBF_ERROR);
+						goto out;
+					}
+
+					break;
+				}
+
+				/* Is there still room in the write buffer to store
+				   more of the string? */
+				if(file->iob_BufferWriteBytes < file->iob_BufferSize)
+				{
+					unsigned char * buffer = &file->iob_Buffer[file->iob_BufferWriteBytes];
+					size_t num_buffer_bytes;
+
+					/* Store only as many characters as will fit into the write buffer. */
+					num_buffer_bytes = file->iob_BufferSize - file->iob_BufferWriteBytes;
+					if(total_size < num_buffer_bytes)
+						num_buffer_bytes = total_size;
+
+					memmove(buffer, s, num_buffer_bytes);
+					s += num_buffer_bytes;
+
+					file->iob_BufferWriteBytes += num_buffer_bytes;
+
+					/* Write a full buffer to disk. */
+					if(__iob_write_buffer_is_full(file) && __flush_iob_write_buffer(file) < 0)
+					{
+						/* Abort with error. */
+						goto out;
+					}
+
+					/* Stop as soon as no further data needs to be written. */
+					total_size -= num_buffer_bytes;
+					if(total_size == 0)
+						break;
+
+					/* If there is again room in the output buffer,
+					   try this optimization again. */
+					if(file->iob_BufferWriteBytes < file->iob_BufferSize)
+						continue;
+				}
+
+				c = (*s++);
+
+				if(__putc_fully_buffered(c,(FILE *)file) == EOF)
+					goto out;
+
+				total_size--;
+			}
+		}
 	}
 
 	result = OK;
@@ -107,7 +250,8 @@ fputs(const char *s, FILE *stream)
 		}
 	}
 
-	funlockfile(stream);
+	if(stream != NULL)
+		funlockfile(stream);
 
 	RETURN(result);
 	return(result);