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diff --git a/man-pages-posix-2003/man1p/readonly.1p b/man-pages-posix-2003/man1p/readonly.1p new file mode 100644 index 0000000..0b3f006 --- /dev/null +++ b/man-pages-posix-2003/man1p/readonly.1p @@ -0,0 +1,156 @@ +.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved +.TH "READONLY" 1P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual" +.\" readonly +.SH PROLOG +This manual page is part of the POSIX Programmer's Manual. +The Linux implementation of this interface may differ (consult +the corresponding Linux manual page for details of Linux behavior), +or the interface may not be implemented on Linux. +.SH NAME +readonly \- set the readonly attribute for variables +.SH SYNOPSIS +.LP +\fBreadonly name\fP\fB[\fP\fB=\fP\fIword\fP\fB]\fP\fB... +.br +.sp +readonly -p +.br +\fP +.SH DESCRIPTION +.LP +The variables whose \fIname\fPs are specified shall be given the \fIreadonly\fP +attribute. The values of variables with the +\fIreadonly\fP attribute cannot be changed by subsequent assignment, +nor can those variables be unset by the \fIunset\fP utility. If the +name of a variable is followed by = \fIword\fP, then the value of +that +variable shall be set to \fIword\fP. +.LP +The \fIreadonly\fP special built-in shall support the Base Definitions +volume of IEEE\ Std\ 1003.1-2001, Section 12.2, Utility Syntax Guidelines. +.LP +When \fB-p\fP is specified, \fIreadonly\fP writes to the standard +output the names and values of all read-only variables, in +the following format: +.sp +.RS +.nf + +\fB"readonly %s=%s\\n", <\fP\fIname\fP\fB>, <\fP\fIvalue\fP\fB> +\fP +.fi +.RE +.LP +if \fIname\fP is set, and +.sp +.RS +.nf + +\fB"readonly %s\\n", <\fP\fIname\fP\fB> +\fP +.fi +.RE +.LP +if \fIname\fP is unset. +.LP +The shell shall format 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 \fIreadonly\fP attribute-setting +results in a shell execution environment in which: +.IP " 1." 4 +Variables with values at the time they were output do not have the +\fIreadonly\fP attribute set. +.LP +.IP " 2." 4 +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. +.LP +.LP +When no arguments are given, the results are unspecified. +.SH OPTIONS +.LP +See the DESCRIPTION. +.SH OPERANDS +.LP +See the DESCRIPTION. +.SH STDIN +.LP +Not used. +.SH INPUT FILES +.LP +None. +.SH ENVIRONMENT VARIABLES +.LP +None. +.SH ASYNCHRONOUS EVENTS +.LP +Default. +.SH STDOUT +.LP +See the DESCRIPTION. +.SH STDERR +.LP +The standard error shall be used only for diagnostic messages. +.SH OUTPUT FILES +.LP +None. +.SH EXTENDED DESCRIPTION +.LP +None. +.SH EXIT STATUS +.LP +Zero. +.SH CONSEQUENCES OF ERRORS +.LP +Default. +.LP +\fIThe following sections are informative.\fP +.SH APPLICATION USAGE +.LP +None. +.SH EXAMPLES +.sp +.RS +.nf + +\fBreadonly HOME PWD +\fP +.fi +.RE +.SH RATIONALE +.LP +Some historical shells preserve the \fIreadonly\fP attribute across +separate invocations. This volume of +IEEE\ Std\ 1003.1-2001 allows this behavior, but does not require +it. +.LP +The \fB-p\fP option allows portable access to the values that can +be saved and then later restored using, for example, a \fIdot\fP script. +Also see the RATIONALE for \fIexport\fP +for a description of the no-argument and \fB-p\fP output cases and +a related example. +.LP +Read-only functions were considered, but they were omitted as not +being historical practice or particularly useful. Furthermore, +functions must not be read-only across invocations to preclude ``spoofing'' +(spoofing is the term for the practice of creating a +program that acts like a well-known utility with the intent of subverting +the real intent of the user) of administrative or +security-relevant (or security-conscious) shell scripts. +.SH FUTURE DIRECTIONS +.LP +None. +.SH SEE ALSO +.LP +\fISpecial Built-In Utilities\fP +.SH COPYRIGHT +Portions of this text are reprinted and reproduced in electronic form +from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology +-- Portable Operating System Interface (POSIX), The Open Group Base +Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of +Electrical and Electronics Engineers, Inc and The Open Group. In the +event of any discrepancy between this version and the original IEEE and +The Open Group Standard, the original IEEE and The Open Group Standard +is the referee document. The original Standard can be obtained online at +http://www.opengroup.org/unix/online.html . |