diff options
Diffstat (limited to 'reference/C/MAN/sysconf.htm')
| -rw-r--r-- | reference/C/MAN/sysconf.htm | 233 |
1 files changed, 233 insertions, 0 deletions
diff --git a/reference/C/MAN/sysconf.htm b/reference/C/MAN/sysconf.htm new file mode 100644 index 0000000..f09ca21 --- /dev/null +++ b/reference/C/MAN/sysconf.htm @@ -0,0 +1,233 @@ +<TITLE>sysconf</TITLE> +<body bgcolor="#ffffcc"> +<hr> +<pre> + + + +<h3>SYSCONF(3) Linux Programmer's Manual SYSCONF(3) +</h3> + +<h3>NAME +</h3> sysconf - Get configuration information at runtime + +<h3>SYNOPSIS +</h3> #include <unistd.h> + + long sysconf(int name); + +<h3>DESCRIPTION +</h3> sysconf() provides a way for the application to determine + values for system limits or options at runtime. + + The equivalent macros defined in <unistd.h> can only give + conservative values; if an application wants to take + advantage of values which may change, a call to sysconf() + can be made, which may yield more liberal results. + + For getting information about a particular file, see + fpathconf() or pathconf(). + + The following values are supported for name. First, the + POSIX.1 compatible values: + + _SC_ARG_MAX + The maximum length of the arguments to the exec() + family of functions; the corresponding macro is + ARG_MAX. + + _SC_CHILD_MAX + The number of simultaneous processes per user id, + the corresponding macro is _POSIX_CHILD_MAX. + + _SC_CLK_TCK + The number of clock ticks per second; the corre- + sponding macro is CLK_TCK. + + _SC_STREAM_MAX + The maximum number of streams that a process can + have open at any time. The corresponding POSIX + macro is STREAM_MAX, the corresponding standard C + macro is FOPEN_MAX. + + _SC_TZNAME_MAX + The maximum number of bytes in a timezone name, the + corresponding macro is TZNAME_MAX. + + _SC_OPEN_MAX + The maximum number of files that a process can have + open at any time, the corresponding macro is + _POSIX_OPEN_MAX. + + _SC_JOB_CONTROL + This indicates whether POSIX - style job control is + supported, the corresponding macro is + + + +<h3>GNU April 18, 1993 1 +</h3> + + + + +<h3>SYSCONF(3) Linux Programmer's Manual SYSCONF(3) +</h3> + + _POSIX_JOB_CONTROL. + + _SC_SAVED_IDS + This indicates whether a process has a saved set- + user-ID and a saved set-group-ID; the corresponding + macro is _POSIX_SAVED_IDS. + + _SC_VERSION + indicates the year and month the POSIX.1 standard + was approved in the format YYYYMML;the value + 199009L indicates the most recent revision, 1990. + + Next, the POSIX.2 values: + + _SC_BC_BASE_MAX + indicates the maximum obase value accepted by the + bc(1) utility; the corresponding macro is + BC_BASE_MAX. + + _SC_BC_DIM_MAX + indicates the maximum value of elements permitted + in an array by bc(1); the corresponding macro is + BC_DIM_MAX. + + _SC_BC_SCALE_MAX + indicates the maximum scale value allowed by bc(1); + the corresponding macro is BC_SCALE_MAX. + + _SC_BC_STRING_MAX + indicates the maximum length of a string accepted + by bc(1); the corresponding macro is BC_STRING_MAX. + + _SC_COLL_WEIGHTS_MAX + indicates the maximum numbers of weights that can + be assigned to an entry of the LC_COLLATE order + keyword in the locale definition file; the corre- + sponding macro is COLL_WEIGHTS_MAX. + + _SC_EXPR_NEST_MAX + is the maximum number of expressions which can be + nested within parentheses by expr(1). The corre- + sponding macro is EXPR_NEST_MAX. + + _SC_LINE_MAX + The maximum length of a utility's input line + length, either from standard input or from a file. + This includes length for a trailing newline. The + corresponding macro is LINE_MAX. + + _SC_RE_DUP_MAX + The maximum number of repeated occurrences of a + regular expression when the interval notation + \{m,n\} is used. The value of the corresponding + macro is RE_DUP_MAX. + + + +<h3>GNU April 18, 1993 2 +</h3> + + + + +<h3>SYSCONF(3) Linux Programmer's Manual SYSCONF(3) +</h3> + + _SC_2_VERSION + indicates the version of the POSIX.2 standard in + the format of YYYYMML. The corresponding macro is + POSIX2_VERSION. + + _SC_2_DEV + indicates whether the POSIX.2 C language develop- + ment facilities are supported. The corresponding + macro is POSIX2_C_DEV. + + _SC_2_FORT_DEV + indicates whether the POSIX.2 FORTRAN development + utilities are supported. The corresponding macro + is POSIX2_FORT_RUN. + + _SC_2_FORT_RUN + indicates whether the POSIX.2 FORTRAN runtime util- + ities are supported. The corresponding macro is + POSIX2_FORT_RUN. + + POSIX2_LOCALEDEF + indicates whether the POSIX.2 creation of locates + via locale(1) is supported. The corresponding + macro is POSIX2_LOCALEDEF. + + _SC_2_SW_DEV + indicates whether the POSIX.2 software development + utilities option is supported. The corresponding + macro is POSIX2_SW_DEV. + +<h3>RETURN VALUE +</h3> The value returned is the value of the system resource, 1 + if a queried option is available, 0 if it is not, or -1 on + error. The variable errno is not set. + +<h3>CONFORMS TO +</h3> POSIX.1, proposed POSIX.2 + +<h3>BUGS +</h3> It is difficult use ARG_MAX because it is not specified + how much of the argument space for exec() is consumed by + the user's environment variables. + + Some returned values may be huge; they are not suitable + for allocating memory. + + POSIX.2 is not yet an approved standard; the information + in this manpage is subject to change. + +</pre> +<hr> +<h3>SEE ALSO +</h3><p> +<a href=bc.htm>bc</a>, +<a href=expr.htm>expr</a>, +<a href=locale.htm>locale</a>, +<a href=fpathconf.htm>fpathconf</a>, +<a href=pathconf.htm>pathconf</a>, +<pre> + + + + + + +<h3>GNU April 18, 1993 3 +</h3> + +
</pre> +<P> +<hr> +<p> +<center> +<table border=2 width=80%> +<tr align=center> +<td width=25%> +<a href=../cref.html>Top</a> +</td><td width=25%> +<a href=../master_index.html>Master Index</a> +</td><td width=25%> +<a href=../SYNTAX/keywords.html>Keywords</a> +</td><td width=25%> +<a href=../FUNCTIONS/funcref.htm>Functions</a> +</td> +</tr> +</table> +</center> +<p> +<hr> + +This manual page was brought to you by <i>mjl_man V-2.0</i> |