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diff --git a/man-pages-posix-2003/man1p/getconf.1p b/man-pages-posix-2003/man1p/getconf.1p new file mode 100644 index 0000000..a13c195 --- /dev/null +++ b/man-pages-posix-2003/man1p/getconf.1p @@ -0,0 +1,464 @@ +.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved +.TH "GETCONF" 1P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual" +.\" getconf +.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 +getconf \- get configuration values +.SH SYNOPSIS +.LP +\fBgetconf\fP \fB[\fP \fB-v specification\fP \fB]\fP \fIsystem_var\fP\fB +.br +.sp +getconf\fP \fB[\fP \fB-v specification\fP \fB]\fP \fIpath_var pathname\fP\fB +.br +\fP +.SH DESCRIPTION +.LP +In the first synopsis form, the \fIgetconf\fP utility shall write +to the standard output the value of the variable specified by +the \fIsystem_var\fP operand. +.LP +In the second synopsis form, the \fIgetconf\fP utility shall write +to the standard output the value of the variable specified +by the \fIpath_var\fP operand for the path specified by the \fIpathname\fP +operand. +.LP +The value of each configuration variable shall be determined as if +it were obtained by calling the function from which it is +defined to be available by this volume of IEEE\ Std\ 1003.1-2001 or +by the System Interfaces volume of +IEEE\ Std\ 1003.1-2001 (see the OPERANDS section). The value shall +reflect conditions in the current operating +environment. +.SH OPTIONS +.LP +The \fIgetconf\fP utility shall conform to the Base Definitions volume +of IEEE\ Std\ 1003.1-2001, Section 12.2, Utility Syntax Guidelines. +.LP +The following option shall be supported: +.TP 7 +\fB-v\ \fP \fIspecification\fP +.sp +Indicate a specific specification and version for which configuration +variables shall be determined. If this option is not +specified, the values returned correspond to an implementation default +conforming compilation environment. +.LP +If the command: +.sp +.RS +.nf + +\fBgetconf _POSIX_V6_ILP32_OFF32 +\fP +.fi +.RE +.LP +does not write \fB"-1\\n"\fP or \fB"undefined\\n"\fP to standard output, +then commands of the form: +.sp +.RS +.nf + +\fBgetconf -v POSIX_V6_ILP32_OFF32 ... +\fP +.fi +.RE +.LP +determine values for configuration variables corresponding to the +POSIX_V6_ILP32_OFF32 compilation environment specified in \fIc99\fP, +the EXTENDED DESCRIPTION. +.LP +If the command: +.sp +.RS +.nf + +\fBgetconf _POSIX_V6_ILP32_OFFBIG +\fP +.fi +.RE +.LP +does not write \fB"-1\\n"\fP or \fB"undefined\\n"\fP to standard output, +then commands of the form: +.sp +.RS +.nf + +\fBgetconf -v POSIX_V6_ILP32_OFFBIG ... +\fP +.fi +.RE +.LP +determine values for configuration variables corresponding to the +POSIX_V6_ILP32_OFFBIG compilation environment specified in \fIc99\fP, +the EXTENDED DESCRIPTION. +.LP +If the command: +.sp +.RS +.nf + +\fBgetconf _POSIX_V6_LP64_OFF64 +\fP +.fi +.RE +.LP +does not write \fB"-1\\n"\fP or \fB"undefined\\n"\fP to standard output, +then commands of the form: +.sp +.RS +.nf + +\fBgetconf -v POSIX_V6_LP64_OFF64 ... +\fP +.fi +.RE +.LP +determine values for configuration variables corresponding to the +POSIX_V6_LP64_OFF64 compilation environment specified in \fIc99\fP, +the EXTENDED DESCRIPTION. +.LP +If the command: +.sp +.RS +.nf + +\fBgetconf _POSIX_V6_LPBIG_OFFBIG +\fP +.fi +.RE +.LP +does not write \fB"-1\\n"\fP or \fB"undefined\\n"\fP to standard output, +then commands of the form: +.sp +.RS +.nf + +\fBgetconf -v POSIX_V6_LPBIG_OFFBIG ... +\fP +.fi +.RE +.LP +determine values for configuration variables corresponding to the +POSIX_V6_LPBIG_OFFBIG compilation environment specified in \fIc99\fP, +the EXTENDED DESCRIPTION. +.sp +.SH OPERANDS +.LP +The following operands shall be supported: +.TP 7 +\fIpath_var\fP +A name of a configuration variable. All of the variables in the Variable +column of the table in the DESCRIPTION of the \fIfpathconf\fP() function +defined in the System Interfaces volume of +IEEE\ Std\ 1003.1-2001, without the enclosing braces, shall be supported. +The implementation may add other local +variables. +.TP 7 +\fIpathname\fP +A pathname for which the variable specified by \fIpath_var\fP is to +be determined. +.TP 7 +\fIsystem_var\fP +A name of a configuration variable. All of the following variables +shall be supported: +.RS +.IP " *" 3 +The names in the Variable column of the table in the DESCRIPTION of +the \fIsysconf\fP() +function in the System Interfaces volume of IEEE\ Std\ 1003.1-2001, +except for the entries corresponding to _SC_CLK_TCK, +_SC_GETGR_R_SIZE_MAX, and _SC_GETPW_R_SIZE_MAX, without the enclosing +braces. +.LP +For compatibility with earlier versions, the following variable names +shall also be supported: +.sp +.RS +.nf + +POSIX2_C_BIND +POSIX2_C_DEV +POSIX2_CHAR_TERM +POSIX2_FORT_DEV +POSIX2_FORT_RUN +POSIX2_LOCALEDEF +POSIX2_SW_DEV +POSIX2_UPE +POSIX2_VERSION +.fi +.RE +.LP +and shall be equivalent to the same name prefixed with an underscore. +This requirement may be removed in a future version. +.LP +.IP " *" 3 +The names of the symbolic constants used as the \fIname\fP argument +of the \fIconfstr\fP() function in the System Interfaces volume of +IEEE\ Std\ 1003.1-2001, +without the _CS_ prefix. +.LP +.IP " *" 3 +The names of the symbolic constants listed under the headings ``Maximum +Values'' and ``Minimum Values'' in the description of +the \fI<limits.h>\fP header in the Base Definitions volume of +IEEE\ Std\ 1003.1-2001, without the enclosing braces. +.LP +For compatibility with earlier versions, the following variable names +shall also be supported: +.sp +.RS +.nf + +POSIX2_BC_BASE_MAX +POSIX2_BC_DIM_MAX +POSIX2_BC_SCALE_MAX +POSIX2_BC_STRING_MAX +POSIX2_COLL_WEIGHTS_MAX +POSIX2_EXPR_NEST_MAX +POSIX2_LINE_MAX +POSIX2_RE_DUP_MAX +.fi +.RE +.LP +and shall be equivalent to the same name prefixed with an underscore. +This requirement may be removed in a future version. +.LP +.RE +.LP +The implementation may add other local values. +.sp +.SH STDIN +.LP +Not used. +.SH INPUT FILES +.LP +None. +.SH ENVIRONMENT VARIABLES +.LP +The following environment variables shall affect the execution of +\fIgetconf\fP: +.TP 7 +\fILANG\fP +Provide a default value for the internationalization variables that +are unset or null. (See the Base Definitions volume of +IEEE\ Std\ 1003.1-2001, Section 8.2, Internationalization Variables +for +the precedence of internationalization variables used to determine +the values of locale categories.) +.TP 7 +\fILC_ALL\fP +If set to a non-empty string value, override the values of all the +other internationalization variables. +.TP 7 +\fILC_CTYPE\fP +Determine the locale for the interpretation of sequences of bytes +of text data as characters (for example, single-byte as +opposed to multi-byte characters in arguments). +.TP 7 +\fILC_MESSAGES\fP +Determine the locale that should be used to affect the format and +contents of diagnostic messages written to standard +error. +.TP 7 +\fINLSPATH\fP +Determine the location of message catalogs for the processing of \fILC_MESSAGES +\&.\fP +.sp +.SH ASYNCHRONOUS EVENTS +.LP +Default. +.SH STDOUT +.LP +If the specified variable is defined on the system and its value is +described to be available from the \fIconfstr\fP() function defined +in the System Interfaces volume of +IEEE\ Std\ 1003.1-2001, its value shall be written in the following +format: +.sp +.RS +.nf + +\fB"%s\\n", <\fP\fIvalue\fP\fB> +\fP +.fi +.RE +.LP +Otherwise, if the specified variable is defined on the system, its +value shall be written in the following format: +.sp +.RS +.nf + +\fB"%d\\n", <\fP\fIvalue\fP\fB> +\fP +.fi +.RE +.LP +If the specified variable is valid, but is undefined on the system, +\fIgetconf\fP shall write using the following format: +.sp +.RS +.nf + +\fB"undefined\\n" +\fP +.fi +.RE +.LP +If the variable name is invalid or an error occurs, nothing shall +be written to standard output. +.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 +The following exit values shall be returned: +.TP 7 +\ 0 +The specified variable is valid and information about its current +state was written successfully. +.TP 7 +>0 +An error occurred. +.sp +.SH CONSEQUENCES OF ERRORS +.LP +Default. +.LP +\fIThe following sections are informative.\fP +.SH APPLICATION USAGE +.LP +None. +.SH EXAMPLES +.LP +The following example illustrates the value of {NGROUPS_MAX}: +.sp +.RS +.nf + +\fBgetconf NGROUPS_MAX +\fP +.fi +.RE +.LP +The following example illustrates the value of {NAME_MAX} for a specific +directory: +.sp +.RS +.nf + +\fBgetconf NAME_MAX /usr +\fP +.fi +.RE +.LP +The following example shows how to deal more carefully with results +that might be unspecified: +.sp +.RS +.nf + +\fBif value=$(getconf PATH_MAX /usr); then + if [ "$value" = "undefined" ]; then + echo PATH_MAX in /usr is infinite. + else + echo PATH_MAX in /usr is $value. + fi +else + echo Error in getconf. +fi +\fP +.fi +.RE +.LP +Note that: +.sp +.RS +.nf + +\fBsysconf(_SC_POSIX_C_BIND); +\fP +.fi +.RE +.LP +and: +.sp +.RS +.nf + +\fBsystem("getconf POSIX2_C_BIND"); +\fP +.fi +.RE +.LP +in a C program could give different answers. The \fIsysconf\fP() call +supplies a value +that corresponds to the conditions when the program was either compiled +or executed, depending on the implementation; the \fIsystem\fP() call +to \fIgetconf\fP always supplies a value corresponding to conditions +when the +program is executed. +.SH RATIONALE +.LP +The original need for this utility, and for the \fIconfstr\fP() function, +was to +provide a way of finding the configuration-defined default value for +the \fIPATH\fP environment variable. Since \fIPATH\fP can be +modified by the user to include directories that could contain utilities +replacing the standard utilities, shell scripts need a way +to determine the system-supplied \fIPATH\fP environment variable value +that contains the correct search path for the standard +utilities. It was later suggested that access to the other variables +described in this volume of IEEE\ Std\ 1003.1-2001 +could also be useful to applications. +.LP +This functionality of \fIgetconf\fP would not be adequately subsumed +by another command such as: +.sp +.RS +.nf + +\fBgrep\fP \fIvar\fP \fB/etc/conf +\fP +.fi +.RE +.LP +because such a strategy would provide correct values for neither those +variables that can vary at runtime, nor those that can +vary depending on the path. +.LP +Early proposal versions of \fIgetconf\fP specified exit status 1 when +the specified variable was valid, but not defined on the +system. The output string \fB"undefined"\fP is now used to specify +this case with exit code 0 because so many things depend on +an exit code of zero when an invoked utility is successful. +.SH FUTURE DIRECTIONS +.LP +None. +.SH SEE ALSO +.LP +\fIc99\fP, the Base Definitions volume of IEEE\ Std\ 1003.1-2001, +\fI<limits.h>\fP, the System Interfaces volume of IEEE\ Std\ 1003.1-2001, +\fIconfstr\fP(), \fIpathconf\fP(), \fIsysconf\fP(), \fIsystem\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 . |