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39 lines
1.2 KiB
Plaintext
39 lines
1.2 KiB
Plaintext
====== The readonly builtin command ======
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===== Synopsis =====
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<code>
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readonly [-p] [-a] [-A] [-f] [NAME[=VALUE] ...]
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</code>
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===== Description =====
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The ''readonly'' builtin command is used to mark variables or functions as read-only, which means unchangeable. This implies that it can't be unset anymore. A ''readonly'' variable may not be redefined in child scopes. A readonly global may not be redefined as a function local variable. Simple command environment assignments may not reference readonly variables.
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==== Options ====
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^Option ^Description ^
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|''-a'' |refer to normal arrays |
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|''-A'' |refer to associative arrays |
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|''-f'' |refer to functions |
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|''-p'' |print all read-only variables or functions, ''-a'', ''-A'' and ''-f'' can be used to filter. The output is reusable as input |
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An argument of ''%%--%%'' disables further option processing.
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==== Return status ====
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^Status ^Reason ^
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|0 |no error |
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|!=0 |invalid option |
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|!=0 |invalid combination of options |
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|!=0 |a given ''NAME'' is invalid |
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===== Examples =====
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===== Portability considerations =====
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* in POSIX(r), only the ''-p'' option is specified
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===== See also =====
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* [[commands:builtin:declare]]
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* [[commands:builtin:unset]] |