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readonly(1)                      User Commands                     readonly(1)



NAME
       readonly  -  shell  built-in function to protect the value of the given
       variable from reassignment

SYNOPSIS
   sh
       readonly [name...]

   ksh
       **readonly [ name [ = value]...]

       **readonly -p

DESCRIPTION
   sh
       The given names are marked readonly and the values of the  these  names
       may not be changed by subsequent assignment. If no arguments are given,
       a list of all readonly names is printed.

   ksh
       The given names are marked readonly and these names cannot  be  changed
       by subsequent assignment.

       When  -p is specified, readonly writes to the standard output the names
       and values of all read-only variables, in the following format:

       "readonly %s=%s\n", name, value

       if name is set, and:

       "readonly $s\n", name

       if name is unset.

       The shell formats the output, including the proper use of  quoting,  so
       that  it  is suitable for reinput to the shell as commands that achieve
       the same value and readonly attribute-setting results in a shell execu-
       tion environment in which:

       1.  Variables  with values set at the time they were output do not have
           the readonly attribute set.


       2.  Variables that were unset at the time they were output do not  have
           a  value  at  the  time at which the saved output is reinput to the
           shell.


       On this man page, ksh(1) commands that are preceded by one  or  two  **
       (asterisks) are treated specially in the following ways:

       1.  Variable  assignment  lists  preceding the command remain in effect
           when the command completes.


       2.  I/O redirections are processed after variable assignments.


       3.  Errors cause a script that contains them to abort.


       4.
           Words, following a command preceded by ** that are in the format of
           a  variable assignment, are expanded with the same rules as a vari-
           able assignment. This means that tilde  substitution  is  performed
           after  the  =  sign and word splitting and file name generation are
           not performed.


ATTRIBUTES
       See attributes(5) for descriptions of the following attributes:


       tab()    allbox;    cw(2.750000i)|     cw(2.750000i)     lw(2.750000i)|
       lw(2.750000i).  ATTRIBUTE TYPEATTRIBUTE VALUE AvailabilitySUNWcsu


SEE ALSO
       ksh(1), sh(1), typeset(1), attributes(5)



SunOS 5.10                        17 Jul 2002                      readonly(1)