ls rwx前文件类型

'-':regular file
'b':block special file
'c':character special file
'C':high performance ("contiguous data") file
'd':directory
'D':door (Solaris 2.5 and up)
'l':symbolic link
'M':off-line ("migrated") file (Cray DMF)
'n':network special file (HP-UX)
'p':FIFO (named pipe)
'P':port (Solaris 10 and up)
's':socket
'?':some other file type