int linkat(int olddirfd, const char *oldpath, int newdirfd, const char *newpath, int flags);
描述The linkat() system call operates in exactly the same way as link(2), except for the differences described in this manual page.
If the pathname given in oldpath is relative, then it is interpreted relative to the directory referred to by the file descriptor olddirfd (rather than relative to the current working directory of the calling process, as is done by link(2) for a relative pathname).
If the pathname given in oldpath is relative and olddirfd is the special value AT_FDCWD, then oldpath is interpreted relative to the current working directory of the calling process (like link(2)).
If the pathname given in oldpath is absolute, then olddirfd is ignored.
The interpretation of newpath is as for oldpath, except that a relative pathname is interpreted relative to the directory referred to by the file descriptor newdirfd.
The flags argument is currently unused, and must be specified as 0.
返回值On success, linkat() returns 0. On error, -1 is returned and errno is set to indicate the error.
错误The same errors that occur for link(2) can also occur for linkat(). The following additional errors can occur for linkat():
|EBADF||olddirfd or newdirfd is not a valid file descriptor.|
|oldpath is a relative path and olddirfd is a file descriptor referring to a file other than a directory; or similar for newpath andnewdirfd|