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


i trying understand line of code means:

flags = fcntl(-1,f_getfl,0);

assuming talking function described man 2 fcntl:

flags = fcntl(-1,f_getfl,0);

tries perform action on invalid file descriptor (-1) , therefore never else returning -1 , set errno ebadf.

i'd can savely replace line by:

flags = -1; errno = ebadf;

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