Hello, VVVa, you wrote: VVV> there is such situation - launched select (he waits state change of sockets) and during this moment there was a need to send the data (happen that the socket is ready to send to a call select) - how to be? - Whether it is possible as - to pull it to write down the data? Nobody hinders to tell to tell there write/send. There registers, how many gets, and if gets nothing, you will receive EWOULDBLOCK (if did not forget to translate, of course, a socket in not locked mode). But in itself such attempt of record breaks nothing, blows up nothing, and your program nobody . A question in if at you half of logically integral piece of the data how then the whirly on select' will understand when not added given to send in addition and when it is possible to send the new registers? Whether to make all around select' (and it is better - around than more modern analog, type poll/epoll, etc.) is easier And if necessity something to send arises not there where select, to organize in storage of queue on sending which the whirly on select' already and rakes?