получить настраиваемые системные переменные (get configurable system variables)
Имя (Name)
sysconf — get configurable system variables
Синопсис (Synopsis)
#include <unistd.h>
long sysconf(int name);
Описание (Description)
The sysconf() function provides a method for the application to
determine the current value of a configurable system limit or
option (variable). The implementation shall support all of the
variables listed in the following table and may support others.
The name argument represents the system variable to be queried.
The following table lists the minimal set of system variables
from <limits.h> or <unistd.h> that can be returned by sysconf(),
and the symbolic constants defined in <unistd.h> that are the
corresponding values used for name.
┌─────────────────────────────────┬──────────────────────────────────┐
│ Variable │ Value of Name │
├─────────────────────────────────┼──────────────────────────────────┤
│{AIO_LISTIO_MAX} │_SC_AIO_LISTIO_MAX │
│{AIO_MAX} │_SC_AIO_MAX │
│{AIO_PRIO_DELTA_MAX} │_SC_AIO_PRIO_DELTA_MAX │
│{ARG_MAX} │_SC_ARG_MAX │
│{ATEXIT_MAX} │_SC_ATEXIT_MAX │
│{BC_BASE_MAX} │_SC_BC_BASE_MAX │
│{BC_DIM_MAX} │_SC_BC_DIM_MAX │
│{BC_SCALE_MAX} │_SC_BC_SCALE_MAX │
│{BC_STRING_MAX} │_SC_BC_STRING_MAX │
│{CHILD_MAX} │_SC_CHILD_MAX │
│Clock ticks/second │_SC_CLK_TCK │
│{COLL_WEIGHTS_MAX} │_SC_COLL_WEIGHTS_MAX │
│{DELAYTIMER_MAX} │_SC_DELAYTIMER_MAX │
│{EXPR_NEST_MAX} │_SC_EXPR_NEST_MAX │
│{HOST_NAME_MAX} │_SC_HOST_NAME_MAX │
│{IOV_MAX} │_SC_IOV_MAX │
│{LINE_MAX} │_SC_LINE_MAX │
│{LOGIN_NAME_MAX} │_SC_LOGIN_NAME_MAX │
│{NGROUPS_MAX} │_SC_NGROUPS_MAX │
│Initial size of getgrgid_r() and │_SC_GETGR_R_SIZE_MAX │
│getgrnam_r() data buffers │ │
│Initial size of getpwuid_r() and │_SC_GETPW_R_SIZE_MAX │
│getpwnam_r() data buffers │ │
│{MQ_OPEN_MAX} │_SC_MQ_OPEN_MAX │
│{MQ_PRIO_MAX} │_SC_MQ_PRIO_MAX │
│{OPEN_MAX} │_SC_OPEN_MAX │
│{PAGE_SIZE} │_SC_PAGE_SIZE │
│{PAGESIZE} │_SC_PAGESIZE │
│{PTHREAD_DESTRUCTOR_ITERATIONS} │_SC_THREAD_DESTRUCTOR_ITERATIONS │
│{PTHREAD_KEYS_MAX} │_SC_THREAD_KEYS_MAX │
│{PTHREAD_STACK_MIN} │_SC_THREAD_STACK_MIN │
│{PTHREAD_THREADS_MAX} │_SC_THREAD_THREADS_MAX │
│{RE_DUP_MAX} │_SC_RE_DUP_MAX │
│{RTSIG_MAX} │_SC_RTSIG_MAX │
│{SEM_NSEMS_MAX} │_SC_SEM_NSEMS_MAX │
│{SEM_VALUE_MAX} │_SC_SEM_VALUE_MAX │
│{SIGQUEUE_MAX} │_SC_SIGQUEUE_MAX │
│{STREAM_MAX} │_SC_STREAM_MAX │
│{SYMLOOP_MAX} │_SC_SYMLOOP_MAX │
│{TIMER_MAX} │_SC_TIMER_MAX │
│{TTY_NAME_MAX} │_SC_TTY_NAME_MAX │
│{TZNAME_MAX} │_SC_TZNAME_MAX │
│_POSIX_ADVISORY_INFO │_SC_ADVISORY_INFO │
│_POSIX_BARRIERS │_SC_BARRIERS │
│_POSIX_ASYNCHRONOUS_IO │_SC_ASYNCHRONOUS_IO │
│_POSIX_CLOCK_SELECTION │_SC_CLOCK_SELECTION │
│_POSIX_CPUTIME │_SC_CPUTIME │
│_POSIX_FSYNC │_SC_FSYNC │
│_POSIX_IPV6 │_SC_IPV6 │
│_POSIX_JOB_CONTROL │_SC_JOB_CONTROL │
│_POSIX_MAPPED_FILES │_SC_MAPPED_FILES │
│_POSIX_MEMLOCK │_SC_MEMLOCK │
│_POSIX_MEMLOCK_RANGE │_SC_MEMLOCK_RANGE │
│_POSIX_MEMORY_PROTECTION │_SC_MEMORY_PROTECTION │
│_POSIX_MESSAGE_PASSING │_SC_MESSAGE_PASSING │
│_POSIX_MONOTONIC_CLOCK │_SC_MONOTONIC_CLOCK │
│_POSIX_PRIORITIZED_IO │_SC_PRIORITIZED_IO │
│_POSIX_PRIORITY_SCHEDULING │_SC_PRIORITY_SCHEDULING │
│_POSIX_RAW_SOCKETS │_SC_RAW_SOCKETS │
│_POSIX_READER_WRITER_LOCKS │_SC_READER_WRITER_LOCKS │
│_POSIX_REALTIME_SIGNALS │_SC_REALTIME_SIGNALS │
│_POSIX_REGEXP │_SC_REGEXP │
│_POSIX_SAVED_IDS │_SC_SAVED_IDS │
│_POSIX_SEMAPHORES │_SC_SEMAPHORES │
│_POSIX_SHARED_MEMORY_OBJECTS │_SC_SHARED_MEMORY_OBJECTS │
│_POSIX_SHELL │_SC_SHELL │
│_POSIX_SPAWN │_SC_SPAWN │
│_POSIX_SPIN_LOCKS │_SC_SPIN_LOCKS │
│_POSIX_SPORADIC_SERVER │_SC_SPORADIC_SERVER │
│_POSIX_SS_REPL_MAX │_SC_SS_REPL_MAX │
│_POSIX_SYNCHRONIZED_IO │_SC_SYNCHRONIZED_IO │
│_POSIX_THREAD_ATTR_STACKADDR │_SC_THREAD_ATTR_STACKADDR │
│_POSIX_THREAD_ATTR_STACKSIZE │_SC_THREAD_ATTR_STACKSIZE │
│_POSIX_THREAD_CPUTIME │_SC_THREAD_CPUTIME │
│_POSIX_THREAD_PRIO_INHERIT │_SC_THREAD_PRIO_INHERIT │
│_POSIX_THREAD_PRIO_PROTECT │_SC_THREAD_PRIO_PROTECT │
│_POSIX_THREAD_PRIORITY_SCHEDULING│_SC_THREAD_PRIORITY_SCHEDULING │
│_POSIX_THREAD_PROCESS_SHARED │_SC_THREAD_PROCESS_SHARED │
│_POSIX_THREAD_ROBUST_PRIO_INHERIT│_SC_THREAD_ROBUST_PRIO_INHERIT │
│_POSIX_THREAD_ROBUST_PRIO_PROTECT│_SC_THREAD_ROBUST_PRIO_PROTECT │
│_POSIX_THREAD_SAFE_FUNCTIONS │_SC_THREAD_SAFE_FUNCTIONS │
│_POSIX_THREAD_SPORADIC_SERVER │_SC_THREAD_SPORADIC_SERVER │
│_POSIX_THREADS │_SC_THREADS │
│_POSIX_TIMEOUTS │_SC_TIMEOUTS │
└─────────────────────────────────┴──────────────────────────────────┘
┌─────────────────────────────┬─────────────────────────────┐
│ Variable │ Value of Name │
├─────────────────────────────┼─────────────────────────────┤
│_POSIX_TIMERS │_SC_TIMERS │
│_POSIX_TRACE │_SC_TRACE │
│_POSIX_TRACE_EVENT_FILTER │_SC_TRACE_EVENT_FILTER │
│_POSIX_TRACE_EVENT_NAME_MAX │_SC_TRACE_EVENT_NAME_MAX │
│_POSIX_TRACE_INHERIT │_SC_TRACE_INHERIT │
│_POSIX_TRACE_LOG │_SC_TRACE_LOG │
│_POSIX_TRACE_NAME_MAX │_SC_TRACE_NAME_MAX │
│_POSIX_TRACE_SYS_MAX │_SC_TRACE_SYS_MAX │
│_POSIX_TRACE_USER_EVENT_MAX │_SC_TRACE_USER_EVENT_MAX │
│_POSIX_TYPED_MEMORY_OBJECTS │_SC_TYPED_MEMORY_OBJECTS │
│_POSIX_VERSION │_SC_VERSION │
│_POSIX_V7_ILP32_OFF32 │_SC_V7_ILP32_OFF32 │
│_POSIX_V7_ILP32_OFFBIG │_SC_V7_ILP32_OFFBIG │
│_POSIX_V7_LP64_OFF64 │_SC_V7_LP64_OFF64 │
│_POSIX_V7_LPBIG_OFFBIG │_SC_V7_LPBIG_OFFBIG │
│_POSIX_V6_ILP32_OFF32 │_SC_V6_ILP32_OFF32 │
│_POSIX_V6_ILP32_OFFBIG │_SC_V6_ILP32_OFFBIG │
│_POSIX_V6_LP64_OFF64 │_SC_V6_LP64_OFF64 │
│_POSIX_V6_LPBIG_OFFBIG │_SC_V6_LPBIG_OFFBIG │
│_POSIX2_C_BIND │_SC_2_C_BIND │
│_POSIX2_C_DEV │_SC_2_C_DEV │
│_POSIX2_CHAR_TERM │_SC_2_CHAR_TERM │
│_POSIX2_FORT_DEV │_SC_2_FORT_DEV │
│_POSIX2_FORT_RUN │_SC_2_FORT_RUN │
│_POSIX2_LOCALEDEF │_SC_2_LOCALEDEF │
│_POSIX2_PBS │_SC_2_PBS │
│_POSIX2_PBS_ACCOUNTING │_SC_2_PBS_ACCOUNTING │
│_POSIX2_PBS_CHECKPOINT │_SC_2_PBS_CHECKPOINT │
│_POSIX2_PBS_LOCATE │_SC_2_PBS_LOCATE │
│_POSIX2_PBS_MESSAGE │_SC_2_PBS_MESSAGE │
│_POSIX2_PBS_TRACK │_SC_2_PBS_TRACK │
│_POSIX2_SW_DEV │_SC_2_SW_DEV │
│_POSIX2_UPE │_SC_2_UPE │
│_POSIX2_VERSION │_SC_2_VERSION │
│_XOPEN_CRYPT │_SC_XOPEN_CRYPT │
│_XOPEN_ENH_I18N │_SC_XOPEN_ENH_I18N │
│_XOPEN_REALTIME │_SC_XOPEN_REALTIME │
│_XOPEN_REALTIME_THREADS │_SC_XOPEN_REALTIME_THREADS │
│_XOPEN_SHM │_SC_XOPEN_SHM │
│_XOPEN_STREAMS │_SC_XOPEN_STREAMS │
│_XOPEN_UNIX │_SC_XOPEN_UNIX │
│_XOPEN_UUCP │_SC_XOPEN_UUCP │
│_XOPEN_VERSION │_SC_XOPEN_VERSION │
└─────────────────────────────┴─────────────────────────────┘
