Is Save Blocking nor non-blocking

[C# Programming]

.Net 1.1

I have a PictureBox with and image loading form string called pb.

Is
pb.Image.Save(SomeOutPutPath) blocking or non blocking?

Also is

File.Save(SomeFile, SomeOtherOutputPath) blocking or non blocking?

I have checked MSDN but there is no notes on this. I would run a test app, but the system I am currently on does not use 1.1

However there is a system that has a 1.1 app and does both saves and is experiencing issues.

Thank you in advance,

"9 Pregnent woman can not have a baby in 1 month" -Uknown