readonly(1) User Commands readonly(1)NAMEreadonly - 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:
┌─────────────────────────────┬─────────────────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
├─────────────────────────────┼─────────────────────────────┤
│Availability │SUNWcsu │
└─────────────────────────────┴─────────────────────────────┘
SEE ALSOksh(1), sh(1), typeset(1), attributes(5)SunOS 5.10 17 Jul 2002 readonly(1)