c++ - Concurrent system calls in Linux -

simple question is, haven't found googling. safe make concurrent calls linux system, such calling socket() on several threads @ (what might be) same time? specifically, kernel guarantee thread-safety socket(), connect(), and/or send()?

if not, why not? i'd learn more topic , why system calls or not thread-safe.

my main concern here socket() not return duplicate or invalid file descriptor when called different threads. i'm not going connecting or writing same socket @ same time in case.

is safe make concurrent calls linux system, such calling socket() on several threads @ (what might be) same time?

yes, thread safe. though not sure per posix standard or not.

specifically, kernel guarantee thread-safety socket(), connect(), and/or send()?

as per this link, yes. says locks used internally, mean send operation serialized, not in specific order.

answer updated part of question:

my main concern here socket() not return duplicate or invalid file descriptor when called different threads.

no worries here. os make sure file descriptors socket not duplicated.