Commit 3907e3b675

@@ -609,3 +609,27 @@ test "c out stream" {
     const out_stream = &io.COutStream.init(out_file).stream;
     try out_stream.print("hi: {}\n", i32(123));
 }
+
+test "File seek ops" {
+    const tmp_file_name = "temp_test_file.txt";
+    var file = try File.openWrite(tmp_file_name);
+    defer {
+        file.close();
+        fs.deleteFile(tmp_file_name) catch {};
+    }
+
+    try file.write([_]u8{0x55} ** 8192);
+
+    // Seek to the end
+    try file.seekFromEnd(0);
+    std.testing.expect((try file.getPos()) == try file.getEndPos());
+    // Negative delta
+    try file.seekBy(-4096);
+    std.testing.expect((try file.getPos()) == 4096);
+    // Positive delta
+    try file.seekBy(10);
+    std.testing.expect((try file.getPos()) == 4106);
+    // Absolute position
+    try file.seekTo(1234);
+    std.testing.expect((try file.getPos()) == 1234);
+}

@@ -2243,7 +2243,8 @@ pub const SeekError = error{
 /// Repositions read/write file offset relative to the beginning.
 pub fn lseek_SET(fd: fd_t, offset: u64) SeekError!void {
     if (linux.is_the_target and !builtin.link_libc and @sizeOf(usize) == 4) {
-        switch (errno(system.llseek(fd, offset, null, SEEK_SET))) {
+        var result: u64 = undefined;
+        switch (errno(system.llseek(fd, offset, &result, SEEK_SET))) {
             0 => return,
             EBADF => unreachable, // always a race condition
             EINVAL => return error.Unseekable,
@@ -2271,7 +2272,8 @@ pub fn lseek_SET(fd: fd_t, offset: u64) SeekError!void {
 /// Repositions read/write file offset relative to the current offset.
 pub fn lseek_CUR(fd: fd_t, offset: i64) SeekError!void {
     if (linux.is_the_target and !builtin.link_libc and @sizeOf(usize) == 4) {
-        switch (errno(system.llseek(fd, @bitCast(u64, offset), null, SEEK_CUR))) {
+        var result: u64 = undefined;
+        switch (errno(system.llseek(fd, @bitCast(u64, offset), &result, SEEK_CUR))) {
             0 => return,
             EBADF => unreachable, // always a race condition
             EINVAL => return error.Unseekable,
@@ -2298,7 +2300,9 @@ pub fn lseek_CUR(fd: fd_t, offset: i64) SeekError!void {
 /// Repositions read/write file offset relative to the end.
 pub fn lseek_END(fd: fd_t, offset: i64) SeekError!void {
     if (linux.is_the_target and !builtin.link_libc and @sizeOf(usize) == 4) {
-        switch (errno(system.llseek(fd, @bitCast(u64, offset), null, SEEK_END))) {
+        var result: u64 = undefined;
+        switch (errno(system.llseek(fd, @bitCast(u64, offset), &result, SEEK_END))) {
+            0 => return,
             EBADF => unreachable, // always a race condition
             EINVAL => return error.Unseekable,
             EOVERFLOW => return error.Unseekable,