constant description "pc_name_max"pc_no_truncmaximum length of filename in directory indicates whether an attempt to create file with name longer than pc_name_max for directory will fail with an enametoolong error maximum length of relative path name when the directory fd is the current working directory size of the pipe buffer when fd refers to pipe or fifo indicates whether priority / can be performed on fd indicates whether synchronous / can be performed on fd indicates whether fd allows special-character processing to be disabled fd must refer to terminal "pc_path_max"pc_pipe_buf"pc_prio_io"pc_sync_io"pc_vdisablenot all names are available on all platformsand some systems may define additional configuration parameters howevera list of the names known to the operating system can be found in the dictionary os pathconf_names if known configuration name is not included in os pathconf_namesits integer value can also be passed as name even if name is recognized by pythonthis function may still raise an oserror if the host operating system doesn' recognize the parameter or associate it with the file fd this function is only available on some versions of unix fstat(fdreturns the status for file descriptor fd returns the same values as the os stat(function (unix and windowsfstatvfs(fdreturns information about the file system containing the file associated with file descriptor fd returns the same values as the os statvfs(function (unixfsync(fdforces any unwritten data on fd to be written to disk note that if you are using an object with buffered / (for examplea python file object)you should first flush the data before calling fsync(available on unix and windows ftruncate(fdlengthtruncates the file corresponding to file descriptor fd so that it' at most length bytes in size (unixisatty(fdreturns true if fd is associated with tty-like device such as terminal (unixlseek(fdposhowsets the current position of file descriptor fd to position pos values of how are as followsseek_set sets the position relative to the beginning of the fileseek_cur sets it relative to the current positionand seek_end sets it relative to the end of the file in older python codeit is common to see these constants replaced with their numeric values of or respectively lib fl ff