Posix/constants-Phpdoc专题
预定义常量
目录
下列常量由此扩展定义,且仅在此扩展编译入 PHP 或在运行时动态载入时可用。
posix_access constants
Note:
These constants are available starting with PHP 5.1.0. Please note that some of them may not be available on your system.
POSIX_F_OK
(int)
Check whether the file exists.
POSIX_R_OK
(int)
Check whether the file exists and has read
permissions.
POSIX_W_OK
(int)
Check whether the file exists and has write
permissions.
POSIX_X_OK
(int)
Check whether the file exists and has execute
permissions.
posix_mknod constants
Note:
These constants are available starting with PHP 5.1.0. Please note that some of them may not be available on your system.
POSIX_S_IFBLK
(int)
Block special file
POSIX_S_IFCHR
(int)
Character special file
POSIX_S_IFIFO
(int)
FIFO (named pipe) special file
POSIX_S_IFREG
(int)
Normal file
POSIX_S_IFSOCK
(int)
Socket
posix_setrlimit constants
Note:
These constants are available starting with PHP 7.0.0. Please note that some of them may not be available on your system.
Note:
You may wish to read the below notes in conjunction with the manpage for setrlimit on your specific operating system, as there is variance in how these limits are interpreted, even across operating systems that claim to implement POSIX in full.
POSIX_RLIMIT_AS
(int)
The maximum size of the process's address space
in bytes. See also PHP's
memory_limit
configuration directive.
POSIX_RLIMIT_CORE
(int)
The maximum size of a core file. If the limit is
set to 0, no core file will be generated.
POSIX_RLIMIT_CPU
(int)
The maximum amount of CPU time that the process
can use, in seconds. When the soft limit is hit, a SIGXCPU signal will
be sent, which can be caught with <span
class="function">pcntl_signal. Depending on the operating
system, additional SIGXCPU signals may be sent each second until the
hard limit is hit, at which point an uncatchable SIGKILL signal is
sent. See also <span
class="function">set_time_limit.
POSIX_RLIMIT_DATA
(int)
The maximum size of the process's data segment,
in bytes. It is extremely unlikely that this will have any effect on the
execution of PHP unless an extension is in use that calls <span
class="function">brk or sbrk.
POSIX_RLIMIT_FSIZE
(int)
The maximum size of files that the process can
create, in bytes.
POSIX_RLIMIT_LOCKS
(int)
The maximum number of locks that the process can
create. This is only supported on extremely old Linux kernels.
POSIX_RLIMIT_MEMLOCK
(int)
The maximum number of bytes that can be locked
into memory.
POSIX_RLIMIT_MSGQUEUE
(int)
The maximum number of bytes that can be allocated
for POSIX message queues. PHP does not ship with support for POSIX
message queues, so this limit will not have any effect unless you are
using an extension that implements that support.
POSIX_RLIMIT_NICE
(int)
The maximum value to which the process can be
reniced to.
The value that will be used will be 20 - limit, as resource limit
values cannot be negative.
POSIX_RLIMIT_NOFILE
(int)
A value one greater than the maximum file
descriptor number that can be opened by this process.
POSIX_RLIMIT_NPROC
(int)
The maximum number of processes (and/or threads,
on some operating systems) that can be created for the real user ID of
the process.
POSIX_RLIMIT_RSS
(int)
The maximum size of the process's resident set,
in pages.
POSIX_RLIMIT_RTPRIO
(int)
The maximum real time priority that can be set
via the sched_setscheduler and <span
class="function">sched_setparam system calls.
POSIX_RLIMIT_RTTIME
(int)
The maximum amount of CPU time, in microseconds,
that the process can consume without making a blocking system call if it
is using real time scheduling.
POSIX_RLIMIT_SIGPENDING
(int)
The maximum number of signals that can be queued
for the real user ID of the process.
POSIX_RLIMIT_STACK
(int)
The maximum size of the process stack, in bytes.
POSIX_RLIMIT_INFINITY
(int)
Used to indicate an infinite value for a resource
limit.