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diff --git a/upstream/archlinux/man3p/getrlimit.3p b/upstream/archlinux/man3p/getrlimit.3p new file mode 100644 index 00000000..e687ffeb --- /dev/null +++ b/upstream/archlinux/man3p/getrlimit.3p @@ -0,0 +1,252 @@ +'\" et +.TH GETRLIMIT "3P" 2017 "IEEE/The Open Group" "POSIX Programmer's Manual" +.\" +.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 +\(em control maximum resource consumption +.SH SYNOPSIS +.LP +.nf +#include <sys/resource.h> +.P +int getrlimit(int \fIresource\fP, struct rlimit *\fIrlp\fP); +int setrlimit(int \fIresource\fP, const struct rlimit *\fIrlp\fP); +.fi +.SH DESCRIPTION +The +\fIgetrlimit\fR() +function shall get, and the +\fIsetrlimit\fR() +function shall set, limits on the consumption of a variety of +resources. +.P +Each call to either +\fIgetrlimit\fR() +or +\fIsetrlimit\fR() +identifies a specific resource to be operated upon as well as a +resource limit. A resource limit is represented by an +.BR rlimit +structure. The +.IR rlim_cur +member specifies the current or soft limit and the +.IR rlim_max +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\fR() +subject to the constraints described above. +.P +The value RLIM_INFINITY, defined in +.IR <sys/resource.h> , +shall be considered to be larger than any other limit value. If a +call to +\fIgetrlimit\fR() +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\fR() +shall inhibit enforcement of that resource limit. +.P +The following resources are defined: +.IP RLIMIT_CORE 14 +This is the maximum size of a +.BR core +file, in bytes, that may be created by a process. A limit of 0 shall +prevent the creation of a +.BR core +file. If this limit is exceeded, the writing of a +.BR core +file shall terminate at this size. +.IP RLIMIT_CPU 14 +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. +.IP RLIMIT_DATA 14 +This is the maximum size of a data segment of the process, in bytes. +If this limit is exceeded, the +\fImalloc\fR() +function shall fail with +.IR errno +set to +.BR [ENOMEM] . +.IP RLIMIT_FSIZE 14 +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 +.IR errno +set to +.BR [EFBIG] . +.IP RLIMIT_NOFILE 14 +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 +.IR errno +set to +.BR [EMFILE] . +This limit constrains the number of file descriptors that a process may +allocate. +.IP RLIMIT_STACK 14 +This is the maximum size of the initial thread's 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. +.IP RLIMIT_AS 14 +This is the maximum size of total available memory of the process, in +bytes. If this limit is exceeded, the +\fImalloc\fR() +and +\fImmap\fR() +functions shall fail with +.IR errno +set to +.BR [ENOMEM] . +In addition, the automatic stack growth fails with the effects outlined +above. +.P +When using the +\fIgetrlimit\fR() +function, if a resource limit can be represented correctly in an object +of type +.BR rlim_t , +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. +.P +When using the +\fIsetrlimit\fR() +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 +.BR rlim_t +then it shall be overwritten with the new limit. +.P +The result of setting a limit to RLIM_SAVED_MAX or RLIM_SAVED_CUR is +unspecified unless a previous call to +\fIgetrlimit\fR() +returned that value as the soft or hard limit for the corresponding +resource limit. +.P +The determination of whether a limit can be correctly represented in an +object of type +.BR rlim_t +is implementation-defined. For example, some implementations permit a +limit whose value is greater than RLIM_INFINITY and others do not. +.P +The +.IR exec +family of functions shall cause resource limits to be saved. +.SH "RETURN VALUE" +Upon successful completion, +\fIgetrlimit\fR() +and +\fIsetrlimit\fR() +shall return 0. Otherwise, these functions shall return \-1 and set +.IR errno +to indicate the error. +.SH ERRORS +The +\fIgetrlimit\fR() +and +\fIsetrlimit\fR() +functions shall fail if: +.TP +.BR EINVAL +An invalid +.IR resource +was specified; or in a +\fIsetrlimit\fR() +call, the new +.IR rlim_cur +exceeds the new +.IR rlim_max . +.TP +.BR EPERM +The limit specified to +\fIsetrlimit\fR() +would have raised the maximum limit value, and the calling process does +not have appropriate privileges. +.P +The +\fIsetrlimit\fR() +function may fail if: +.TP +.BR EINVAL +The limit specified cannot be lowered because current usage is already +higher than the limit. +.LP +.IR "The following sections are informative." +.SH EXAMPLES +None. +.SH "APPLICATION USAGE" +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 +.IR <limits.h> , +unexpected behavior may occur. +.P +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 +It should be noted that RLIMIT_STACK applies ``at least'' to the stack +of the initial thread in the process, and not to the sum of all the +stacks in the process, as that would be very limiting unless the value +is so big as to provide no value at all with a single thread. +.SH "FUTURE DIRECTIONS" +None. +.SH "SEE ALSO" +.IR "\fIexec\fR\^", +.IR "\fIfork\fR\^(\|)", +.IR "\fImalloc\fR\^(\|)", +.IR "\fIopen\fR\^(\|)", +.IR "\fIsigaltstack\fR\^(\|)", +.IR "\fIsysconf\fR\^(\|)", +.IR "\fIulimit\fR\^(\|)" +.P +The Base Definitions volume of POSIX.1\(hy2017, +.IR "\fB<stropts.h>\fP", +.IR "\fB<sys_resource.h>\fP" +.\" +.SH COPYRIGHT +Portions of this text are reprinted and reproduced in electronic form +from IEEE Std 1003.1-2017, Standard for Information Technology +-- Portable Operating System Interface (POSIX), The Open Group Base +Specifications Issue 7, 2018 Edition, +Copyright (C) 2018 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 . +.PP +Any typographical or formatting errors that appear +in this page are most likely +to have been introduced during the conversion of the source files to +man page format. To report such errors, see +https://www.kernel.org/doc/man-pages/reporting_bugs.html . |