SYNOPSIS<\/a>
DESCRIPTION<\/a>
RETURN VALUE<\/a>
ERRORS<\/a>
ATTRIBUTES<\/a>
CONFORMING TO<\/a>
NOTES<\/a>
SEE ALSO<\/a>
COLOPHON<\/a> <\/p>\n
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NAME <\/a> <\/h2>\nfpathconf, pathconf \u2212 get configuration values for files<\/p>\n
SYNOPSIS <\/a> <\/h2>\n#include <\/b><\/p>\nlong fpathconf(int<\/b> fd<\/i>, int<\/b> name<\/i>);
long pathconf(const char *<\/b>path<\/i>, int<\/b> name<\/i>);<\/b><\/p>\nDESCRIPTION <\/a> <\/h2>\nfpathconf<\/b>() gets a value for the configuration option name<\/i> for the open file descriptor fd<\/i>.<\/p>\n
pathconf<\/b>() gets a value for configuration option name<\/i> for the filename path<\/i>.<\/p>\n
The corresponding macros defined in <\/i> are minimum values; if an application wants to take advantage of values which may change, a call to fpathconf<\/b>() or pathconf<\/b>() can be made, which may yield more liberal results.<\/p>\nSetting name<\/i> equal to one of the following constants returns the following configuration options:
_PC_LINK_MAX<\/b><\/p>\n
The maximum number of links to the file. If fd<\/i> or path<\/i> refer to a directory, then the value applies to the whole directory. The corresponding macro is _POSIX_LINK_MAX<\/b>.<\/p>\n
_PC_MAX_CANON<\/b><\/p>\n
The maximum length of a formatted input line, where fd<\/i> or path<\/i> must refer to a terminal. The corresponding macro is _POSIX_MAX_CANON<\/b>.<\/p>\n
_PC_MAX_INPUT<\/b><\/p>\n
The maximum length of an input line, where fd<\/i> or path<\/i> must refer to a terminal. The corresponding macro is _POSIX_MAX_INPUT<\/b>.<\/p>\n
_PC_NAME_MAX<\/b><\/p>\n
The maximum length of a filename in the directory path<\/i> or fd<\/i> that the process is allowed to create. The corresponding macro is _POSIX_NAME_MAX<\/b>.<\/p>\n
_PC_PATH_MAX<\/b><\/p>\n
The maximum length of a relative pathname when path<\/i> or fd<\/i> is the current working directory. The corresponding macro is _POSIX_PATH_MAX<\/b>.<\/p>\n
_PC_PIPE_BUF<\/b><\/p>\n
The maximum number of bytes that can be written atomically to a pipe of FIFO. For fpathconf<\/b>(), fd<\/i> should refer to a pipe or FIFO. For fpathconf<\/b>(), path<\/i> should refer to a FIFO or a directory; in the latter case, the returned value corresponds to FIFOs created in that directory. The corresponding macro is _POSIX_PIPE_BUF<\/b>.<\/p>\n
_PC_CHOWN_RESTRICTED<\/b><\/p>\n
This returns a positive value if the use of chown<\/b>(2) and fchown<\/b>(2) for changing a file\u2019s user ID is restricted to a process with appropriate privileges, and changing a file\u2019s group ID to a value other than the process\u2019s effective group ID or one of its supplementary group IDs is restricted to a process with appropriate privileges. According to POSIX.1, this variable shall always be defined with a value other than \u22121. The corresponding macro is _POSIX_CHOWN_RESTRICTED<\/b>.<\/p>\n
If fd<\/i> or path<\/i> refers to a directory, then the return value applies to all files in that directory.<\/p>\n
_PC_NO_TRUNC<\/b><\/p>\n
This returns nonzero if accessing filenames longer than _POSIX_NAME_MAX<\/b> generates an error. The corresponding macro is _POSIX_NO_TRUNC<\/b>.<\/p>\n
_PC_VDISABLE<\/b><\/p>\n
This returns nonzero if special character processing can be disabled, where fd<\/i> or path<\/i> must refer to a terminal.<\/p>\nRETURN VALUE <\/a> <\/h2>\nThe return value of these functions is one of the following:<\/p>\n
\n\n<\/td>\n \n*<\/p>\n<\/td>\n
<\/td>\n \nOn error, \u22121 is returned and errno<\/i> is set to indicate the cause of the error (for example, EINVAL<\/b>, indicating that name<\/i> is invalid).<\/p>\n<\/td>\n<\/tr>\n\n<\/td>\n \n*<\/p>\n<\/td>\n
<\/td>\n \nIf name<\/i> corresponds to a maximum or minimum limit, and that limit is indeterminate, \u22121 is returned and errno<\/i> is not changed. (To distinguish an indeterminate limit from an error, set errno<\/i> to zero before the call, and then check whether errno<\/i> is nonzero when \u22121 is returned.)<\/p>\n<\/td>\n<\/tr>\n\n<\/td>\n \n*<\/p>\n<\/td>\n
<\/td>\n \nIf name<\/i> corresponds to an option, a positive value is returned if the option is supported, and \u22121 is returned if the option is not supported.<\/p>\n<\/td>\n<\/tr>\n\n<\/td>\n \n*<\/p>\n<\/td>\n
<\/td>\n \nOtherwise, the current value of the option or limit is returned. This value will not be more restrictive than the corresponding value that was described to the application in <\/i> or <\/i> when the application was compiled.<\/p>\n<\/td>\n<\/tr>\n<\/table>\nERRORS <\/a> <\/h2>\n
#include long fpathconf(int<\/b> fd<\/i>, int<\/b> name<\/i>); fpathconf<\/b>() gets a value for the configuration option name<\/i> for the open file descriptor fd<\/i>.<\/p>\n pathconf<\/b>() gets a value for configuration option name<\/i> for the filename path<\/i>.<\/p>\n The corresponding macros defined in Setting name<\/i> equal to one of the following constants returns the following configuration options: The maximum number of links to the file. If fd<\/i> or path<\/i> refer to a directory, then the value applies to the whole directory. The corresponding macro is _POSIX_LINK_MAX<\/b>.<\/p>\n _PC_MAX_CANON<\/b><\/p>\n The maximum length of a formatted input line, where fd<\/i> or path<\/i> must refer to a terminal. The corresponding macro is _POSIX_MAX_CANON<\/b>.<\/p>\n _PC_MAX_INPUT<\/b><\/p>\n The maximum length of an input line, where fd<\/i> or path<\/i> must refer to a terminal. The corresponding macro is _POSIX_MAX_INPUT<\/b>.<\/p>\n _PC_NAME_MAX<\/b><\/p>\n The maximum length of a filename in the directory path<\/i> or fd<\/i> that the process is allowed to create. The corresponding macro is _POSIX_NAME_MAX<\/b>.<\/p>\n _PC_PATH_MAX<\/b><\/p>\n The maximum length of a relative pathname when path<\/i> or fd<\/i> is the current working directory. The corresponding macro is _POSIX_PATH_MAX<\/b>.<\/p>\n _PC_PIPE_BUF<\/b><\/p>\n The maximum number of bytes that can be written atomically to a pipe of FIFO. For fpathconf<\/b>(), fd<\/i> should refer to a pipe or FIFO. For fpathconf<\/b>(), path<\/i> should refer to a FIFO or a directory; in the latter case, the returned value corresponds to FIFOs created in that directory. The corresponding macro is _POSIX_PIPE_BUF<\/b>.<\/p>\n _PC_CHOWN_RESTRICTED<\/b><\/p>\n This returns a positive value if the use of chown<\/b>(2) and fchown<\/b>(2) for changing a file\u2019s user ID is restricted to a process with appropriate privileges, and changing a file\u2019s group ID to a value other than the process\u2019s effective group ID or one of its supplementary group IDs is restricted to a process with appropriate privileges. According to POSIX.1, this variable shall always be defined with a value other than \u22121. The corresponding macro is _POSIX_CHOWN_RESTRICTED<\/b>.<\/p>\n If fd<\/i> or path<\/i> refers to a directory, then the return value applies to all files in that directory.<\/p>\n _PC_NO_TRUNC<\/b><\/p>\n This returns nonzero if accessing filenames longer than _POSIX_NAME_MAX<\/b> generates an error. The corresponding macro is _POSIX_NO_TRUNC<\/b>.<\/p>\n _PC_VDISABLE<\/b><\/p>\n This returns nonzero if special character processing can be disabled, where fd<\/i> or path<\/i> must refer to a terminal.<\/p>\n The return value of these functions is one of the following:<\/p>\n *<\/p>\n<\/td>\n On error, \u22121 is returned and errno<\/i> is set to indicate the cause of the error (for example, EINVAL<\/b>, indicating that name<\/i> is invalid).<\/p>\n<\/td>\n<\/tr>\n *<\/p>\n<\/td>\n If name<\/i> corresponds to a maximum or minimum limit, and that limit is indeterminate, \u22121 is returned and errno<\/i> is not changed. (To distinguish an indeterminate limit from an error, set errno<\/i> to zero before the call, and then check whether errno<\/i> is nonzero when \u22121 is returned.)<\/p>\n<\/td>\n<\/tr>\n *<\/p>\n<\/td>\n If name<\/i> corresponds to an option, a positive value is returned if the option is supported, and \u22121 is returned if the option is not supported.<\/p>\n<\/td>\n<\/tr>\n *<\/p>\n<\/td>\n Otherwise, the current value of the option or limit is returned. This value will not be more restrictive than the corresponding value that was described to the application in
long pathconf(const char *<\/b>path<\/i>, int<\/b> name<\/i>);<\/b><\/p>\nDESCRIPTION <\/a> <\/h2>\n
_PC_LINK_MAX<\/b><\/p>\nRETURN VALUE <\/a> <\/h2>\n
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\n <\/td>\n \n <\/td>\n \n \n <\/td>\n \n <\/td>\n \n \n <\/td>\n \n <\/td>\n \n \n <\/td>\n \n <\/td>\n \n ERRORS <\/a> <\/h2>\n
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