Try again if write(2) reports an recoverable error.
Try again if write(2) reports an recoverable error.

This should fix mysteriously crashing boost regression tests when stderr is
managed by bjam (PR7043).


git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@103085 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/llvm,llvm-mirror/llvm,llvm-mirror/llvm,dslab-epfl/asap,dslab-epfl/asap,llvm-mirror/llvm,dslab-epfl/asap,chubbymaggie/asap,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,apple/swift-llvm,apple/swift-llvm,chubbymaggie/asap,GPUOpen-Drivers/llvm,dslab-epfl/asap,llvm-mirror/llvm,apple/swift-llvm,dslab-epfl/asap,apple/swift-llvm,dslab-epfl/asap,apple/swift-llvm,chubbymaggie/asap,llvm-mirror/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,llvm-mirror/llvm,apple/swift-llvm,apple/swift-llvm,llvm-mirror/llvm,chubbymaggie/asap,dslab-epfl/asap,apple/swift-llvm,GPUOpen-Drivers/llvm,chubbymaggie/asap,GPUOpen-Drivers/llvm,chubbymaggie/asap,GPUOpen-Drivers/llvm,llvm-mirror/llvm