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The default setting for µC/TCP-IP is blocking. However, this setting can be changed at compile time by setting the NET_SOCK_DFLT_NO_BLOCK_EN to DEF_ENABLED or DEF_DISABLED. (see netsee net_cfg.h file).
DEF_DISABLED sets the blocking mode to blocking. This means that a socket receive function will wait forever, until at least one byte of data is available to return or the socket connection is closed, unless a timeout is specified by NetSock_CfgTimeoutRxQ_Set() [See function NetSock_CfgTimeoutRxQ_Set()].
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