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DESCRIPTION<\/a>
RETURN VALUE<\/a>
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EXAMPLES<\/a>
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COLOPHON<\/a> <\/p>\n
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NAME <\/a> <\/h2>\nconfstr \u2212 get configuration dependent string variables<\/p>\n
SYNOPSIS <\/a> <\/h2>\n#include <\/b><\/p>\nsize_t confstr(int<\/b> name<\/i>, char *<\/b>buf<\/i>, size_t<\/b> len<\/i>);<\/b><\/p>\n
Feature Test Macro Requirements for glibc (see feature_test_macros<\/b>(7)):<\/p>\n
confstr<\/b>(): _POSIX_C_SOURCE\u00a0>=\u00a02 || _XOPEN_SOURCE<\/p>\nDESCRIPTION <\/a> <\/h2>\nconfstr<\/b>() gets the value of configuration-dependent string variables.<\/p>\n
The name<\/i> argument is the system variable to be queried. The following variables are supported:
_CS_GNU_LIBC_VERSION<\/b> (GNU C library only; since glibc 2.3.2)<\/p>\n
A string which identifies the GNU C library version on this system (e.g., “glibc 2.3.4”).<\/p>\n
_CS_GNU_LIBPTHREAD_VERSION<\/b> (GNU C library only; since glibc 2.3.2)<\/p>\n
A string which identifies the POSIX implementation supplied by this C library (e.g., “NPTL 2.3.4” or “linuxthreads-0.10”).<\/p>\n
_CS_PATH<\/b><\/p>\n
A value for the PATH<\/b> variable which indicates where all the POSIX.2 standard utilities can be found.<\/p>\n
If buf<\/i> is not NULL and len<\/i> is not zero, confstr<\/b>() copies the value of the string to buf<\/i> truncated to len \u2212 1<\/i> bytes if necessary, with a null byte (‘\u0000’) as terminator. This can be detected by comparing the return value of confstr<\/b>() against len<\/i>.<\/p>\n
If len<\/i> is zero and buf<\/i> is NULL, confstr<\/b>() just returns the value as defined below.<\/p>\nRETURN VALUE <\/a> <\/h2>\nIf name<\/i> is a valid configuration variable, confstr<\/b>() returns the number of bytes (including the terminating null byte) that would be required to hold the entire value of that variable. This value may be greater than len<\/i>, which means that the value in buf<\/i> is truncated.<\/p>\n
If name<\/i> is a valid configuration variable, but that variable does not have a value, then confstr<\/b>() returns 0. If name<\/i> does not correspond to a valid configuration variable, confstr<\/b>() returns 0, and errno<\/i> is set to EINVAL<\/b>.<\/p>\nERRORS <\/a> <\/h2>\n
#include size_t confstr(int<\/b> name<\/i>, char *<\/b>buf<\/i>, size_t<\/b> len<\/i>);<\/b><\/p>\n Feature Test Macro Requirements for glibc (see feature_test_macros<\/b>(7)):<\/p>\n confstr<\/b>(): _POSIX_C_SOURCE\u00a0>=\u00a02 || _XOPEN_SOURCE<\/p>\n confstr<\/b>() gets the value of configuration-dependent string variables.<\/p>\n The name<\/i> argument is the system variable to be queried. The following variables are supported: A string which identifies the GNU C library version on this system (e.g., “glibc 2.3.4”).<\/p>\n _CS_GNU_LIBPTHREAD_VERSION<\/b> (GNU C library only; since glibc 2.3.2)<\/p>\n A string which identifies the POSIX implementation supplied by this C library (e.g., “NPTL 2.3.4” or “linuxthreads-0.10”).<\/p>\n _CS_PATH<\/b><\/p>\n A value for the PATH<\/b> variable which indicates where all the POSIX.2 standard utilities can be found.<\/p>\n If buf<\/i> is not NULL and len<\/i> is not zero, confstr<\/b>() copies the value of the string to buf<\/i> truncated to len \u2212 1<\/i> bytes if necessary, with a null byte (‘\u0000’) as terminator. This can be detected by comparing the return value of confstr<\/b>() against len<\/i>.<\/p>\n If len<\/i> is zero and buf<\/i> is NULL, confstr<\/b>() just returns the value as defined below.<\/p>\n If name<\/i> is a valid configuration variable, confstr<\/b>() returns the number of bytes (including the terminating null byte) that would be required to hold the entire value of that variable. This value may be greater than len<\/i>, which means that the value in buf<\/i> is truncated.<\/p>\n If name<\/i> is a valid configuration variable, but that variable does not have a value, then confstr<\/b>() returns 0. If name<\/i> does not correspond to a valid configuration variable, confstr<\/b>() returns 0, and errno<\/i> is set to EINVAL<\/b>.<\/p>\nDESCRIPTION <\/a> <\/h2>\n
_CS_GNU_LIBC_VERSION<\/b> (GNU C library only; since glibc 2.3.2)<\/p>\nRETURN VALUE <\/a> <\/h2>\n
ERRORS <\/a> <\/h2>\n
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