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diff --git a/man3/sysconf.3 b/man3/sysconf.3 deleted file mode 100644 index 1010caa8c..000000000 --- a/man3/sysconf.3 +++ /dev/null @@ -1,390 +0,0 @@ -'\" t -.\" Copyright (c) 1993 by Thomas Koenig (ig25@rz.uni-karlsruhe.de) -.\" -.\" SPDX-License-Identifier: Linux-man-pages-copyleft -.\" -.\" Modified Sat Jul 24 17:51:42 1993 by Rik Faith (faith@cs.unc.edu) -.\" Modified Tue Aug 17 11:42:20 1999 by Ariel Scolnicov (ariels@compugen.co.il) -.TH sysconf 3 (date) "Linux man-pages (unreleased)" -.SH NAME -sysconf \- get configuration information at run time -.SH LIBRARY -Standard C library -.RI ( libc ", " \-lc ) -.SH SYNOPSIS -.nf -.B #include <unistd.h> -.P -.BI "long sysconf(int " "name" ); -.fi -.SH DESCRIPTION -POSIX allows an application to test at compile or run time -whether certain options are supported, or what the value is -of certain configurable constants or limits. -.P -At compile time this is done by including -.I <unistd.h> -and/or -.I <limits.h> -and testing the value of certain macros. -.P -At run time, one can ask for numerical values using the present function -.BR sysconf (). -One can ask for numerical values that may depend -on the filesystem in which a file resides using -.BR fpathconf (3) -and -.BR pathconf (3). -One can ask for string values using -.BR confstr (3). -.P -The values obtained from these functions are system configuration constants. -They do not change during the lifetime of a process. -.\" except that sysconf(_SC_OPEN_MAX) may change answer after a call -.\" to setrlimit( ) which changes the RLIMIT_NOFILE soft limit -.P -For options, typically, there is a constant -.B _POSIX_FOO -that may be defined in -.IR <unistd.h> . -If it is undefined, one should ask at run time. -If it is defined to \-1, then the option is not supported. -If it is defined to 0, then relevant functions and headers exist, -but one has to ask at run time what degree of support is available. -If it is defined to a value other than \-1 or 0, then the option is -supported. -Usually the value (such as 200112L) indicates the year and month -of the POSIX revision describing the option. -glibc uses the value 1 -to indicate support as long as the POSIX revision has not been published yet. -.\" and 999 to indicate support for options no longer present in the latest -.\" standard. (?) -The -.BR sysconf () -argument will be -.BR _SC_FOO . -For a list of options, see -.BR posixoptions (7). -.P -For variables or limits, typically, there is a constant -.BR _FOO , -maybe defined in -.IR <limits.h> , -or -.BR _POSIX_FOO , -maybe defined in -.IR <unistd.h> . -The constant will not be defined if the limit is unspecified. -If the constant is defined, it gives a guaranteed value, and -a greater value might actually be supported. -If an application wants to take advantage of values which may change -between systems, a call to -.BR sysconf () -can be made. -The -.BR sysconf () -argument will be -.BR _SC_FOO . -.SS POSIX.1 variables -We give the name of the variable, the name of the -.BR sysconf () -argument used to inquire about its value, -and a short description. -.P -First, the POSIX.1 compatible values. -.\" [for the moment: only the things that are unconditionally present] -.\" .TP -.\" .BR AIO_LISTIO_MAX " - " _SC_AIO_LISTIO_MAX -.\" (if _POSIX_ASYNCHRONOUS_IO) -.\" Maximum number of I/O operations in a single list I/O call. -.\" Must not be less than _POSIX_AIO_LISTIO_MAX. -.\" .TP -.\" .BR AIO_MAX " - " _SC_AIO_MAX -.\" (if _POSIX_ASYNCHRONOUS_IO) -.\" Maximum number of outstanding asynchronous I/O operations. -.\" Must not be less than _POSIX_AIO_MAX. -.\" .TP -.\" .BR AIO_PRIO_DELTA_MAX " - " _SC_AIO_PRIO_DELTA_MAX -.\" (if _POSIX_ASYNCHRONOUS_IO) -.\" The maximum amount by which a process can decrease its -.\" asynchronous I/O priority level from its own scheduling priority. -.\" Must be nonnegative. -.TP -.BR ARG_MAX " - " _SC_ARG_MAX -The maximum length of the arguments to the -.BR exec (3) -family of functions. -Must not be less than -.B _POSIX_ARG_MAX -(4096). -.TP -.BR CHILD_MAX " - " _SC_CHILD_MAX -The maximum number of simultaneous processes per user ID. -Must not be less than -.B _POSIX_CHILD_MAX -(25). -.TP -.BR HOST_NAME_MAX " - " _SC_HOST_NAME_MAX -Maximum length of a hostname, not including the terminating null byte, -as returned by -.BR gethostname (2). -Must not be less than -.B _POSIX_HOST_NAME_MAX -(255). -.TP -.BR LOGIN_NAME_MAX " - " _SC_LOGIN_NAME_MAX -Maximum length of a login name, including the terminating null byte. -Must not be less than -.B _POSIX_LOGIN_NAME_MAX -(9). -.TP -.BR NGROUPS_MAX " - " _SC_NGROUPS_MAX -Maximum number of supplementary group IDs. -.TP -.BR "" "clock ticks - " _SC_CLK_TCK -The number of clock ticks per second. -The corresponding variable is obsolete. -It was of course called -.BR CLK_TCK . -(Note: the macro -.B CLOCKS_PER_SEC -does not give information: it must equal 1000000.) -.TP -.BR OPEN_MAX " - " _SC_OPEN_MAX -The maximum number of files that a process can have open at any time. -Must not be less than -.B _POSIX_OPEN_MAX -(20). -.TP -.BR PAGESIZE " - " _SC_PAGESIZE -Size of a page in bytes. -Must not be less than 1. -.TP -.BR PAGE_SIZE " - " _SC_PAGE_SIZE -A synonym for -.BR PAGESIZE / _SC_PAGESIZE . -(Both -.B PAGESIZE -and -.B PAGE_SIZE -are specified in POSIX.) -.TP -.BR RE_DUP_MAX " - " _SC_RE_DUP_MAX -The number of repeated occurrences of a BRE permitted by -.BR regexec (3) -and -.BR regcomp (3). -Must not be less than -.B _POSIX2_RE_DUP_MAX -(255). -.TP -.BR STREAM_MAX " - " _SC_STREAM_MAX -The maximum number of streams that a process can have open at any -time. -If defined, it has the same value as the standard C macro -.BR FOPEN_MAX . -Must not be less than -.B _POSIX_STREAM_MAX -(8). -.TP -.BR SYMLOOP_MAX " - " _SC_SYMLOOP_MAX -The maximum number of symbolic links seen in a pathname before resolution -returns -.BR ELOOP . -Must not be less than -.B _POSIX_SYMLOOP_MAX -(8). -.TP -.BR TTY_NAME_MAX " - " _SC_TTY_NAME_MAX -The maximum length of terminal device name, -including the terminating null byte. -Must not be less than -.B _POSIX_TTY_NAME_MAX -(9). -.TP -.BR TZNAME_MAX " - " _SC_TZNAME_MAX -The maximum number of bytes in a timezone name. -Must not be less than -.B _POSIX_TZNAME_MAX -(6). -.TP -.BR _POSIX_VERSION " - " _SC_VERSION -indicates the year and month the POSIX.1 standard was approved in the -format -.BR YYYYMML ; -the value -.B 199009L -indicates the Sept. 1990 revision. -.SS POSIX.2 variables -Next, the POSIX.2 values, giving limits for utilities. -.TP -.BR BC_BASE_MAX " - " _SC_BC_BASE_MAX -indicates the maximum -.I obase -value accepted by the -.BR bc (1) -utility. -.TP -.BR BC_DIM_MAX " - " _SC_BC_DIM_MAX -indicates the maximum value of elements permitted in an array by -.BR bc (1). -.TP -.BR BC_SCALE_MAX " - " _SC_BC_SCALE_MAX -indicates the maximum -.I scale -value allowed by -.BR bc (1). -.TP -.BR BC_STRING_MAX " - " _SC_BC_STRING_MAX -indicates the maximum length of a string accepted by -.BR bc (1). -.TP -.BR COLL_WEIGHTS_MAX " - " _SC_COLL_WEIGHTS_MAX -indicates the maximum numbers of weights that can be assigned to an -entry of the -.B LC_COLLATE order -keyword in the locale definition file. -.TP -.BR EXPR_NEST_MAX " - " _SC_EXPR_NEST_MAX -is the maximum number of expressions which can be nested within -parentheses by -.BR expr (1). -.TP -.BR LINE_MAX " - " _SC_LINE_MAX -The maximum length of a utility's input line, either from -standard input or from a file. -This includes space for a trailing -newline. -.TP -.BR RE_DUP_MAX " - " _SC_RE_DUP_MAX -The maximum number of repeated occurrences of a regular expression when -the interval notation -.B \e{m,n\e} -is used. -.TP -.BR POSIX2_VERSION " - " _SC_2_VERSION -indicates the version of the POSIX.2 standard in the format of -YYYYMML. -.TP -.BR POSIX2_C_DEV " - " _SC_2_C_DEV -indicates whether the POSIX.2 C language development facilities are -supported. -.TP -.BR POSIX2_FORT_DEV " - " _SC_2_FORT_DEV -indicates whether the POSIX.2 FORTRAN development utilities are -supported. -.TP -.BR POSIX2_FORT_RUN " - " _SC_2_FORT_RUN -indicates whether the POSIX.2 FORTRAN run-time utilities are supported. -.TP -.BR _POSIX2_LOCALEDEF " - " _SC_2_LOCALEDEF -indicates whether the POSIX.2 creation of locales via -.BR localedef (1) -is supported. -.TP -.BR POSIX2_SW_DEV " - " _SC_2_SW_DEV -indicates whether the POSIX.2 software development utilities option is -supported. -.P -These values also exist, but may not be standard. -.TP -.BR "" " - " _SC_PHYS_PAGES -The number of pages of physical memory. -Note that it is possible -for the product of this value and the value of -.B _SC_PAGESIZE -to overflow. -.TP -.BR "" " - " _SC_AVPHYS_PAGES -The number of currently available pages of physical memory. -.TP -.BR "" " - " _SC_NPROCESSORS_CONF -The number of processors configured. -See also -.BR get_nprocs_conf (3). -.TP -.BR "" " - " _SC_NPROCESSORS_ONLN -The number of processors currently online (available). -See also -.BR get_nprocs_conf (3). -.SH RETURN VALUE -The return value of -.BR sysconf () -is one of the following: -.IP \[bu] 3 -On error, \-1 is returned and -.I errno -is set to indicate the error -(for example, -.BR EINVAL , -indicating that -.I name -is invalid). -.IP \[bu] -If -.I name -corresponds to a maximum or minimum limit, and that limit is indeterminate, -\-1 is returned and -.I errno -is not changed. -(To distinguish an indeterminate limit from an error, set -.I errno -to zero before the call, and then check whether -.I errno -is nonzero when \-1 is returned.) -.IP \[bu] -If -.I name -corresponds to an option, -a positive value is returned if the option is supported, -and \-1 is returned if the option is not supported. -.IP \[bu] -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 -.I <unistd.h> -or -.I <limits.h> -when the application was compiled. -.SH ERRORS -.TP -.B EINVAL -.I name -is invalid. -.SH ATTRIBUTES -For an explanation of the terms used in this section, see -.BR attributes (7). -.TS -allbox; -lbx lb lb -l l l. -Interface Attribute Value -T{ -.na -.nh -.BR sysconf () -T} Thread safety MT-Safe env -.TE -.SH STANDARDS -POSIX.1-2008. -.SH HISTORY -POSIX.1-2001. -.SH BUGS -It is difficult to use -.B ARG_MAX -because it is not specified how much of the argument space for -.BR exec (3) -is consumed by the user's environment variables. -.P -Some returned values may be huge; they are not suitable for allocating -memory. -.SH SEE ALSO -.BR bc (1), -.BR expr (1), -.BR getconf (1), -.BR locale (1), -.BR confstr (3), -.BR fpathconf (3), -.BR pathconf (3), -.BR posixoptions (7) |