The linux kernel itself appears to never generate this error message.
The POSIX standard says:
Bad message. During a read( ), getmsg( ), getpmsg( ), or ioctl( ) I_RECVFD request to a STREAMS device, a message arrived at the head of the STREAM that is inappropriate for the function receiving the message. read( ) Message waiting to be read on a STREAM is not a data message.
No page links to EBADMSG.
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