Commit d680b9e9b2

Andrew Kelley <andrew@ziglang.org>
2025-10-14 04:04:02
std.Io.File: add WouldBlock to the error set
Even in an asynchronous world, the concept of a non-blocking flag is useful because it determines under what conditions the operation completes.
master
1 parent 5398082
Changed files (2)
lib
std
Io
File.zig
Threaded.zig
lib/std/Io/File.zig
@@ -139,6 +139,8 @@ pub const OpenError = error{
     ///   kernel (e.g., for module/firmware loading), and write access was
     ///   requested.
     FileBusy,
+    /// Non-blocking was requested and the operation cannot return immediately.
+    WouldBlock,
 } || Io.Dir.PathNameError || Io.Cancelable || Io.UnexpectedError;
 
 pub fn close(file: File, io: Io) void {
lib/std/Io/Threaded.zig
@@ -1039,7 +1039,7 @@ fn dirCreateFilePosix(
             .EXIST => return error.PathAlreadyExists,
             .BUSY => return error.DeviceBusy,
             .OPNOTSUPP => return error.FileLocksNotSupported,
-            //.AGAIN => return error.WouldBlock,
+            .AGAIN => return error.WouldBlock,
             .TXTBSY => return error.FileBusy,
             .NXIO => return error.NoDevice,
             .ILSEQ => return error.BadPathName,
@@ -1064,7 +1064,7 @@ fn dirCreateFilePosix(
                 .BADF => |err| return errnoBug(err),
                 .INVAL => |err| return errnoBug(err), // invalid parameters
                 .NOLCK => return error.SystemResources,
-                //.AGAIN => return error.WouldBlock,
+                .AGAIN => return error.WouldBlock,
                 .OPNOTSUPP => return error.FileLocksNotSupported,
                 else => |err| return posix.unexpectedErrno(err),
             }
@@ -1168,7 +1168,7 @@ fn dirOpenFile(
             .EXIST => return error.PathAlreadyExists,
             .BUSY => return error.DeviceBusy,
             .OPNOTSUPP => return error.FileLocksNotSupported,
-            //.AGAIN => return error.WouldBlock,
+            .AGAIN => return error.WouldBlock,
             .TXTBSY => return error.FileBusy,
             .NXIO => return error.NoDevice,
             .ILSEQ => return error.BadPathName,
@@ -1193,7 +1193,7 @@ fn dirOpenFile(
                 .BADF => |err| return errnoBug(err),
                 .INVAL => |err| return errnoBug(err), // invalid parameters
                 .NOLCK => return error.SystemResources,
-                //.AGAIN => return error.WouldBlock,
+                .AGAIN => return error.WouldBlock,
                 .OPNOTSUPP => return error.FileLocksNotSupported,
                 else => |err| return posix.unexpectedErrno(err),
             }