What is the purpose of calling fcntl() be called with the file descriptor as -1 and cmd as F_GETFL?

What is the purpose of calling fcntl() be called with the file descriptor as -1 and cmd as F_GETFL?

c sockets unix freebsd fcntl

unix

Are POSIX file locks reentrant?

c unix locking posix fcntl

unix

when is the arg for F_GETFL fcntl command required?

c linux unix freebsd fcntl

unix

How to create symbolic link to a path that contains unicode characters?

c unix unicode symlink fcntl

unix

Difference between select() and fcntl()

c unix select file-descriptor fcntl

unix

file lock in unix system using c and fcntl

c unix fcntl

unix

What is the compelling use case for the FD_CLOEXEC flag?

linux unix fopen fcntl

unix