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diff --git a/man-pages-posix-2003/man3p/getrlimit.3p b/man-pages-posix-2003/man3p/getrlimit.3p new file mode 100644 index 0000000..a58c63e --- /dev/null +++ b/man-pages-posix-2003/man3p/getrlimit.3p @@ -0,0 +1,194 @@ +.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved +.TH "GETRLIMIT" 3P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual" +.\" getrlimit +.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 +getrlimit, setrlimit \- control maximum resource consumption +.SH SYNOPSIS +.LP +\fB#include <sys/resource.h> +.br +.sp +int getrlimit(int\fP \fIresource\fP\fB, struct rlimit *\fP\fIrlp\fP\fB); +.br +int setrlimit(int\fP \fIresource\fP\fB, const struct rlimit *\fP\fIrlp\fP\fB); +\fP +\fB +.br +\fP +.SH DESCRIPTION +.LP +The \fIgetrlimit\fP() function shall get, and the \fIsetrlimit\fP() +function shall set, limits on the consumption of a variety +of resources. +.LP +Each call to either \fIgetrlimit\fP() or \fIsetrlimit\fP() identifies +a specific resource to be operated upon as well as a +resource limit. A resource limit is represented by an \fBrlimit\fP +structure. The \fIrlim_cur\fP member specifies the current or +soft limit and the \fIrlim_max\fP member specifies the maximum or +hard limit. Soft limits may be changed by a process to any value +that is less than or equal to the hard limit. A process may (irreversibly) +lower its hard limit to any value that is greater than +or equal to the soft limit. Only a process with appropriate privileges +can raise a hard limit. Both hard and soft limits can be +changed in a single call to \fIsetrlimit\fP() subject to the constraints +described above. +.LP +The value RLIM_INFINITY, defined in \fI<sys/resource.h>\fP, shall +be +considered to be larger than any other limit value. If a call to \fIgetrlimit\fP() +returns RLIM_INFINITY for a resource, it means +the implementation shall not enforce limits on that resource. Specifying +RLIM_INFINITY as any resource limit value on a successful +call to \fIsetrlimit\fP() shall inhibit enforcement of that resource +limit. +.LP +The following resources are defined: +.TP 7 +RLIMIT_CORE +This is the maximum size of a \fBcore\fP file, in bytes, that may +be created by a process. A limit of 0 shall prevent the +creation of a \fBcore\fP file. If this limit is exceeded, the writing +of a \fBcore\fP file shall terminate at this size. +.TP 7 +RLIMIT_CPU +This is the maximum amount of CPU time, in seconds, used by a process. +If this limit is exceeded, SIGXCPU shall be generated +for the process. If the process is catching or ignoring SIGXCPU, or +all threads belonging to that process are blocking SIGXCPU, the +behavior is unspecified. +.TP 7 +RLIMIT_DATA +This is the maximum size of a process' data segment, in bytes. If +this limit is exceeded, the \fImalloc\fP() function shall fail with +\fIerrno\fP set to [ENOMEM]. +.TP 7 +RLIMIT_FSIZE +This is the maximum size of a file, in bytes, that may be created +by a process. If a write or truncate operation would cause +this limit to be exceeded, SIGXFSZ shall be generated for the thread. +If the thread is blocking, or the process is catching or +ignoring SIGXFSZ, continued attempts to increase the size of a file +from end-of-file to beyond the limit shall fail with +\fIerrno\fP set to [EFBIG]. +.TP 7 +RLIMIT_NOFILE +This is a number one greater than the maximum value that the system +may assign to a newly-created descriptor. If this limit is +exceeded, functions that allocate a file descriptor shall fail with +\fIerrno\fP set to [EMFILE]. This limit constrains the number +of file descriptors that a process may allocate. +.TP 7 +RLIMIT_STACK +This is the maximum size of a process' stack, in bytes. The implementation +does not automatically grow the stack beyond this +limit. If this limit is exceeded, SIGSEGV shall be generated for the +thread. If the thread is blocking SIGSEGV, or the process is +ignoring or catching SIGSEGV and has not made arrangements to use +an alternate stack, the disposition of SIGSEGV shall be set to +SIG_DFL before it is generated. +.TP 7 +RLIMIT_AS +This is the maximum size of a process' total available memory, in +bytes. If this limit is exceeded, the \fImalloc\fP() and \fImmap\fP() +functions shall fail with +\fIerrno\fP set to [ENOMEM]. In addition, the automatic stack growth +fails with the effects outlined above. +.sp +.LP +When using the \fIgetrlimit\fP() function, if a resource limit can +be represented correctly in an object of type \fBrlim_t\fP, +then its representation is returned; otherwise, if the value of the +resource limit is equal to that of the corresponding saved hard +limit, the value returned shall be RLIM_SAVED_MAX; otherwise, the +value returned shall be RLIM_SAVED_CUR. +.LP +When using the \fIsetrlimit\fP() function, if the requested new limit +is RLIM_INFINITY, the new limit shall be "no limit''; +otherwise, if the requested new limit is RLIM_SAVED_MAX, the new limit +shall be the corresponding saved hard limit; otherwise, if +the requested new limit is RLIM_SAVED_CUR, the new limit shall be +the corresponding saved soft limit; otherwise, the new limit +shall be the requested value. In addition, if the corresponding saved +limit can be represented correctly in an object of type +\fBrlim_t\fP then it shall be overwritten with the new limit. +.LP +The result of setting a limit to RLIM_SAVED_MAX or RLIM_SAVED_CUR +is unspecified unless a previous call to \fIgetrlimit\fP() +returned that value as the soft or hard limit for the corresponding +resource limit. +.LP +The determination of whether a limit can be correctly represented +in an object of type \fBrlim_t\fP is implementation-defined. +For example, some implementations permit a limit whose value is greater +than RLIM_INFINITY and others do not. +.LP +The \fIexec\fP family of functions shall cause resource limits to +be saved. +.SH RETURN VALUE +.LP +Upon successful completion, \fIgetrlimit\fP() and \fIsetrlimit\fP() +shall return 0. Otherwise, these functions shall return -1 +and set \fIerrno\fP to indicate the error. +.SH ERRORS +.LP +The \fIgetrlimit\fP() and \fIsetrlimit\fP() functions shall fail if: +.TP 7 +.B EINVAL +An invalid \fIresource\fP was specified; or in a \fIsetrlimit\fP() +call, the new \fIrlim_cur\fP exceeds the new +\fIrlim_max\fP. +.TP 7 +.B EPERM +The limit specified to \fIsetrlimit\fP() would have raised the maximum +limit value, and the calling process does not have +appropriate privileges. +.sp +.LP +The \fIsetrlimit\fP() function may fail if: +.TP 7 +.B EINVAL +The limit specified cannot be lowered because current usage is already +higher than the limit. +.sp +.LP +\fIThe following sections are informative.\fP +.SH EXAMPLES +.LP +None. +.SH APPLICATION USAGE +.LP +If a process attempts to set the hard limit or soft limit for RLIMIT_NOFILE +to less than the value of {_POSIX_OPEN_MAX} from \fI<limits.h>\fP, +unexpected behavior may occur. +.LP +If a process attempts to set the hard limit or soft limit for RLIMIT_NOFILE +to less than the highest currently open file +descriptor +1, unexpected behavior may occur. +.SH RATIONALE +.LP +None. +.SH FUTURE DIRECTIONS +.LP +None. +.SH SEE ALSO +.LP +\fIexec\fP(), \fIfork\fP(), \fImalloc\fP(), \fIopen\fP(), \fIsigaltstack\fP() +, +\fIsysconf\fP(), \fIulimit\fP(), the Base Definitions volume of +IEEE\ Std\ 1003.1-2001, \fI<stropts.h>\fP, \fI<sys/resource.h>\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 . |