WSAEINPROGRESS - 10036 (0x2734)

A blocking operation is currently executing.

Updated: Feb 21, 2026

Technical Meaning

The error code WSAEINPROGRESS (10036, 0x2734) indicates that a blocking operation is currently executing. This typically occurs in the context of network programming and socket operations.

Error Details

This error code is returned by various Windows Sockets (Winsock) functions when an attempt is made to perform an operation on a socket that is already engaged in another blocking operation. For example, attempting to bind or connect a socket while it is still performing a previous binding or connecting operation will result in this error.

Usage Context

WSAEINPROGRESS is commonly encountered when working with network sockets in applications that require asynchronous operations. It is important for developers to understand the implications of blocking operations and how they can be managed effectively.

Developer Interpretation

When encountering WSAEINPROGRESS, it indicates that a previous operation on the socket has not yet completed, and another attempt to perform an operation on the same socket will result in this error. Developers should ensure that their code handles such scenarios appropriately by checking for this error and retrying operations as necessary.

Related Errors

FAQ

Q: What does WSAEINPROGRESS mean?

A: It indicates that a blocking operation is currently executing on the socket, and another attempt to perform an operation will result in this error.

Q: How can I handle WSAEINPROGRESS errors?

A: Ensure that your code checks for WSAEINPROGRESS and retries operations as necessary when encountering this error.

Summary

The WSAEINPROGRESS error code is a specific technical indicator used in Windows Sockets programming to inform developers that a blocking operation is currently executing. Understanding its implications and handling it appropriately is crucial for developing robust network applications.