fsendfile(): Break ABI by switching src and dst to match rest of API.

Signed-off-by: Joachim Nilsson <troglobit@gmail.com>

README.md

@@ -63,6 +63,11 @@ Generic Functions
   names: files and directories that must be freed after use.  See
   the unit test at the bottom for an example.
 
+- `fcopyfile(src, dst)`
+
+  Like `copyfile()` but uses already open `FILE *` pointers.  Copies
+  from current file positions to current file positions until EOF.
+
 - `fexist(file)`
 
   Check for the existance of a file, returns True(1) or False(0).
@@ -75,6 +80,18 @@ Generic Functions
 
   Returns the `mode_t` bits of a file or directory.
 
+- `fsendfile(src, dst, len)`
+
+  Copy data between file streams, very similar to `fcopyfile()`, but
+  `dst` is allowed to be `NULL` to be able to read and discard `len`
+  bytes from `src`.
+
+- `movefile(src, dst)`
+
+  Like `copyfile()`, but renames `src` to `dst`, or recreates symlink
+  with the `dst` name.  On successful operation the source is removed
+  and the function returns POSIX OK (0).
+
 - `rsync(src, dst, delete, *filter())`
 
   Very simple `rsync()` to copy files files and directories

fsendfile.c

@@ -28,8 +28,8 @@
 
 /**
  * fsendfile - copy data between file streams
- * @dst: Destination stream
  * @src: Source stream
+ * @dst: Destination stream
  * @len: Number of bytes to copy
  *
  * @dst may be %NULL, in which case @len bytes are read and discarded
@@ -41,7 +41,7 @@
  * The number of bytes copied.  If an error is detected -1 is returned
  * and @errno will be set accordingly.
  */
-size_t fsendfile(FILE *dst, FILE *src, size_t len)
+size_t fsendfile(FILE *src, FILE *dst, size_t len)
 {
 	char *buf;
 	size_t blk = BUFSIZ, num = 0, tot = 0;
@@ -94,7 +94,7 @@ int main(void)
                 src = fopen(files[i], "r");
                 dst = fopen(files[i + 1], "w");
 		fprintf(stderr, "fsendfile(%s, %s, 512)\t", files[i], files[i + 1]);
-		if (-1 == fsendfile(dst, src, 512))
+		if (-1 == fsendfile(src, dst, 512))
 			perror("Failed");
 
 		if (!access(files[i + 1], F_OK))

lite.h

@@ -43,7 +43,7 @@ FILE   *tempfile   (void);
 ssize_t copyfile   (char *src, char *dst, int len, int sym);
 int     movefile   (char *src, char *dst);
 int     fcopyfile  (FILE *src, FILE *dst);
-size_t  fsendfile  (FILE *out, FILE *in, size_t sz);
+size_t  fsendfile  (FILE *src, FILE *dst, size_t len);
 
 int     dir        (const char *dir, const char *type, int (*filter) (const char *file), char ***list, int strip);
 int     rsync      (char *src, char *dst, int delete, int (*filter) (const char *file));