#598 Add file IO flush function

CHANGELOG.md

@@ -36,6 +36,7 @@ and this project does not currently adhere to a particular versioning scheme.
 - Add local definitions to imperative syntax. ([#562][gh-562])
 - Add local definitions to functional syntax.
 - Add repeated field name error message.
+- Add primitive file IO function `IO/FS/flush`. ([#598][gh-598])
 
 ## [0.2.35] - 2024-06-06
 
@@ -369,3 +370,4 @@ and this project does not currently adhere to a particular versioning scheme.
 [gh-583]: https://github.com/HigherOrderCO/Bend/issues/583
 [gh-586]: https://github.com/HigherOrderCO/Bend/issues/586
 [gh-596]: https://github.com/HigherOrderCO/Bend/issues/596
+[gh-598]: https://github.com/HigherOrderCO/Bend/issues/598

docs/builtins.md

@@ -426,6 +426,16 @@ Moves the current position of the file with the given `file` descriptor to the g
 
 Returns nothing (`*`).
 
+#### File flush
+
+```python
+def IO/FS/flush(file)
+```
+
+Flushes the file with the given `file` descriptor.
+
+Returns nothing (`*`).
+
 ## Numeric operations
 
 ### log

src/fun/builtins.bend

@@ -128,6 +128,7 @@ IO/FS/close file = (IO/Call IO/MAGIC "CLOSE" file @x (IO/Done IO/MAGIC x))
 IO/FS/read file num_bytes = (IO/Call IO/MAGIC "READ" (file, num_bytes) @x (IO/Done IO/MAGIC x))
 IO/FS/write file bytes = (IO/Call IO/MAGIC "WRITE" (file, bytes) @x (IO/Done IO/MAGIC x))
 IO/FS/seek file offset mode = (IO/Call IO/MAGIC "SEEK" (file, (offset, mode)) @x (IO/Done IO/MAGIC x))
+IO/FS/flush file = (IO/Call IO/MAGIC "FLUSH" file @x (IO/Done IO/MAGIC x))
 
 ### Always available files
 IO/FS/STDIN = 0