alias [ -gmrL ] [ name[=value] ... ]
       For each name with a corresponding value, define an
       alias  with  that value.  A trailing space in value
       causes the next word to be checked for  alias  sub-
       stitution.   If  the  -g  flag is present, define a
       global alias; global aliases are expanded  even  if
       they do not occur in command position.

       For  each  name  with  no value, print the value of
       name, if any.  With no arguments,  print  all  cur-
       rently  defined  aliases.   If the -m flag is given
       the arguments are taken as patterns (they should be
       quoted  to  preserve them from being interpreted as
       glob patterns), and the aliases matching these pat-
       terns  are  printed.  When printing aliases and the
       -g or -r  flags  are  present,  then  restrict  the
       printing  to  global  or  regular  aliases, respec-
       tively.

       If the -L flag is present, then print each alias in
       a  manner suitable for putting in a startup script.
       The exit status is  nonzero  if  a  name  (with  no
       value)  is  given  for  which  no  alias  has  been
       defined.
