getconf 是 glibc 带的一个命令，可以用来查看使用 sysconf，pathconf和confstr函数 设置的各种变量和路径的值。例如：PATH 路径，OS 字大小 LONG_BIT，内存页大小 PAGESIZE 等变量。
$ getconf PAGESIZE
4096
$ getconf -a
LINK_MAX 65000
_POSIX_LINK_MAX 65000
MAX_CANON 255
_POSIX_MAX_CANON 255
MAX_INPUT 255
_POSIX_MAX_INPUT 255
NAME_MAX 255
_POSIX_NAME_MAX 255
PATH_MAX 4096
_POSIX_PATH_MAX 4096
PIPE_BUF 4096
_POSIX_PIPE_BUF 4096
SOCK_MAXBUF
_POSIX_ASYNC_IO
_POSIX_CHOWN_RESTRICTED 1
_POSIX_NO_TRUNC 1
_POSIX_PRIO_IO
_POSIX_SYNC_IO
_POSIX_VDISABLE 0
ARG_MAX 2097152
ATEXIT_MAX 2147483647
CHAR_BIT 8
CHAR_MAX 127
CHAR_MIN -128
CHILD_MAX 127579
CLK_TCK 100
INT_MAX 2147483647
INT_MIN -2147483648
IOV_MAX 1024
LOGNAME_MAX 256
LONG_BIT 64
MB_LEN_MAX 16
NGROUPS_MAX 65536
NL_ARGMAX 4096
NL_LANGMAX 2048
NL_MSGMAX 2147483647
NL_NMAX 2147483647
NL_SETMAX 2147483647
NL_TEXTMAX 2147483647
NSS_BUFLEN_GROUP 1024
NSS_BUFLEN_PASSWD 1024
NZERO 20
OPEN_MAX 1024
PAGESIZE 4096
PAGE_SIZE 4096
PASS_MAX 8192
PTHREAD_DESTRUCTOR_ITERATIONS 4
PTHREAD_KEYS_MAX 1024
PTHREAD_STACK_MIN 16384
PTHREAD_THREADS_MAX
SCHAR_MAX 127
SCHAR_MIN -128
SHRT_MAX 32767
SHRT_MIN -32768
SSIZE_MAX 32767
TTY_NAME_MAX 32
TZNAME_MAX 6
UCHAR_MAX 255
UINT_MAX 4294967295
UIO_MAXIOV 1024
ULONG_MAX 18446744073709551615
USHRT_MAX 65535
WORD_BIT 32
_AVPHYS_PAGES 1047786
_NPROCESSORS_CONF 8
_NPROCESSORS_ONLN 8
_PHYS_PAGES 4091854
_POSIX_ARG_MAX 2097152
_POSIX_ASYNCHRONOUS_IO 200809
_POSIX_CHILD_MAX 127579
_POSIX_FSYNC 200809
_POSIX_JOB_CONTROL 1
_POSIX_MAPPED_FILES 200809
_POSIX_MEMLOCK 200809
_POSIX_MEMLOCK_RANGE 200809
_POSIX_MEMORY_PROTECTION 200809
_POSIX_MESSAGE_PASSING 200809
_POSIX_NGROUPS_MAX 65536
_POSIX_OPEN_MAX 1024
_POSIX_PII
_POSIX_PII_INTERNET
_POSIX_PII_INTERNET_DGRAM
_POSIX_PII_INTERNET_STREAM
_POSIX_PII_OSI
_POSIX_PII_OSI_CLTS
_POSIX_PII_OSI_COTS
_POSIX_PII_OSI_M
_POSIX_PII_SOCKET
_POSIX_PII_XTI
_POSIX_POLL
_POSIX_PRIORITIZED_IO 200809
_POSIX_PRIORITY_SCHEDULING 200809
_POSIX_REALTIME_SIGNALS 200809
_POSIX_SAVED_IDS 1
_POSIX_SELECT
_POSIX_SEMAPHORES 200809
_POSIX_SHARED_MEMORY_OBJECTS 200809
_POSIX_SSIZE_MAX 32767
_POSIX_STREAM_MAX 16
_POSIX_SYNCHRONIZED_IO 200809
_POSIX_THREADS 200809
_POSIX_THREAD_ATTR_STACKADDR 200809
_POSIX_THREAD_ATTR_STACKSIZE 200809
_POSIX_THREAD_PRIORITY_SCHEDULING 200809
_POSIX_THREAD_PRIO_INHERIT 200809
_POSIX_THREAD_PRIO_PROTECT 200809
_POSIX_THREAD_ROBUST_PRIO_INHERIT
_POSIX_THREAD_ROBUST_PRIO_PROTECT
_POSIX_THREAD_PROCESS_SHARED 200809
_POSIX_THREAD_SAFE_FUNCTIONS 200809
_POSIX_TIMERS 200809
TIMER_MAX
_POSIX_TZNAME_MAX 6
_POSIX_VERSION 200809
_T_IOV_MAX
_XOPEN_CRYPT 1
_XOPEN_ENH_I18N 1
_XOPEN_LEGACY 1
_XOPEN_REALTIME 1
_XOPEN_REALTIME_THREADS 1
_XOPEN_SHM 1
_XOPEN_UNIX 1
_XOPEN_VERSION 700
_XOPEN_XCU_VERSION 4
_XOPEN_XPG2 1
_XOPEN_XPG3 1
_XOPEN_XPG4 1
BC_BASE_MAX 99
BC_DIM_MAX 2048
BC_SCALE_MAX 99
BC_STRING_MAX 1000
CHARCLASS_NAME_MAX 2048
COLL_WEIGHTS_MAX 255
EQUIV_CLASS_MAX
EXPR_NEST_MAX 32
LINE_MAX 2048
POSIX2_BC_BASE_MAX 99
POSIX2_BC_DIM_MAX 2048
POSIX2_BC_SCALE_MAX 99
POSIX2_BC_STRING_MAX 1000
POSIX2_CHAR_TERM 200809
POSIX2_COLL_WEIGHTS_MAX 255
POSIX2_C_BIND 200809
POSIX2_C_DEV 200809
POSIX2_C_VERSION
POSIX2_EXPR_NEST_MAX 32
POSIX2_FORT_DEV
POSIX2_FORT_RUN
_POSIX2_LINE_MAX 2048
POSIX2_LINE_MAX 2048
POSIX2_LOCALEDEF 200809
POSIX2_RE_DUP_MAX 32767
POSIX2_SW_DEV 200809
POSIX2_UPE
POSIX2_VERSION 200809
RE_DUP_MAX 32767
PATH /bin:/usr/bin
CS_PATH /bin:/usr/bin
LFS_CFLAGS
LFS_LDFLAGS
LFS_LIBS
LFS_LINTFLAGS
LFS64_CFLAGS -D_LARGEFILE64_SOURCE
LFS64_LDFLAGS
LFS64_LIBS
LFS64_LINTFLAGS -D_LARGEFILE64_SOURCE
_XBS5_WIDTH_RESTRICTED_ENVS XBS5_ILP32_OFF32
XBS5_ILP32_OFFBIG
XBS5_LP64_OFF64
XBS5_WIDTH_RESTRICTED_ENVS XBS5_ILP32_OFF32
XBS5_ILP32_OFFBIG
XBS5_LP64_OFF64
_XBS5_ILP32_OFF32 1
XBS5_ILP32_OFF32_CFLAGS -m32
XBS5_ILP32_OFF32_LDFLAGS -m32
XBS5_ILP32_OFF32_LIBS
XBS5_ILP32_OFF32_LINTFLAGS
_XBS5_ILP32_OFFBIG 1
XBS5_ILP32_OFFBIG_CFLAGS -m32 -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64
XBS5_ILP32_OFFBIG_LDFLAGS -m32
XBS5_ILP32_OFFBIG_LIBS
XBS5_ILP32_OFFBIG_LINTFLAGS
_XBS5_LP64_OFF64 1
XBS5_LP64_OFF64_CFLAGS -m64
XBS5_LP64_OFF64_LDFLAGS -m64
XBS5_LP64_OFF64_LIBS
XBS5_LP64_OFF64_LINTFLAGS
_XBS5_LPBIG_OFFBIG
XBS5_LPBIG_OFFBIG_CFLAGS
XBS5_LPBIG_OFFBIG_LDFLAGS
XBS5_LPBIG_OFFBIG_LIBS
XBS5_LPBIG_OFFBIG_LINTFLAGS
_POSIX_V6_ILP32_OFF32 1
POSIX_V6_ILP32_OFF32_CFLAGS -m32
POSIX_V6_ILP32_OFF32_LDFLAGS -m32
POSIX_V6_ILP32_OFF32_LIBS
POSIX_V6_ILP32_OFF32_LINTFLAGS
_POSIX_V6_WIDTH_RESTRICTED_ENVS POSIX_V6_ILP32_OFF32
POSIX_V6_ILP32_OFFBIG
POSIX_V6_LP64_OFF64
POSIX_V6_WIDTH_RESTRICTED_ENVS POSIX_V6_ILP32_OFF32
POSIX_V6_ILP32_OFFBIG
POSIX_V6_LP64_OFF64
_POSIX_V6_ILP32_OFFBIG 1
POSIX_V6_ILP32_OFFBIG_CFLAGS -m32 -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64
POSIX_V6_ILP32_OFFBIG_LDFLAGS -m32
POSIX_V6_ILP32_OFFBIG_LIBS
POSIX_V6_ILP32_OFFBIG_LINTFLAGS
_POSIX_V6_LP64_OFF64 1
POSIX_V6_LP64_OFF64_CFLAGS -m64
POSIX_V6_LP64_OFF64_LDFLAGS -m64
POSIX_V6_LP64_OFF64_LIBS
POSIX_V6_LP64_OFF64_LINTFLAGS
_POSIX_V6_LPBIG_OFFBIG
POSIX_V6_LPBIG_OFFBIG_CFLAGS
POSIX_V6_LPBIG_OFFBIG_LDFLAGS
POSIX_V6_LPBIG_OFFBIG_LIBS
POSIX_V6_LPBIG_OFFBIG_LINTFLAGS
_POSIX_V7_ILP32_OFF32 1
POSIX_V7_ILP32_OFF32_CFLAGS -m32
POSIX_V7_ILP32_OFF32_LDFLAGS -m32
POSIX_V7_ILP32_OFF32_LIBS
POSIX_V7_ILP32_OFF32_LINTFLAGS
_POSIX_V7_WIDTH_RESTRICTED_ENVS POSIX_V7_ILP32_OFF32
POSIX_V7_ILP32_OFFBIG
POSIX_V7_LP64_OFF64
POSIX_V7_WIDTH_RESTRICTED_ENVS POSIX_V7_ILP32_OFF32
POSIX_V7_ILP32_OFFBIG
POSIX_V7_LP64_OFF64
_POSIX_V7_ILP32_OFFBIG 1
POSIX_V7_ILP32_OFFBIG_CFLAGS -m32 -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64
POSIX_V7_ILP32_OFFBIG_LDFLAGS -m32
POSIX_V7_ILP32_OFFBIG_LIBS
POSIX_V7_ILP32_OFFBIG_LINTFLAGS
_POSIX_V7_LP64_OFF64 1
POSIX_V7_LP64_OFF64_CFLAGS -m64
POSIX_V7_LP64_OFF64_LDFLAGS -m64
POSIX_V7_LP64_OFF64_LIBS
POSIX_V7_LP64_OFF64_LINTFLAGS
_POSIX_V7_LPBIG_OFFBIG
POSIX_V7_LPBIG_OFFBIG_CFLAGS
POSIX_V7_LPBIG_OFFBIG_LDFLAGS
POSIX_V7_LPBIG_OFFBIG_LIBS
POSIX_V7_LPBIG_OFFBIG_LINTFLAGS
_POSIX_ADVISORY_INFO 200809
_POSIX_BARRIERS 200809
_POSIX_BASE
_POSIX_C_LANG_SUPPORT
_POSIX_C_LANG_SUPPORT_R
_POSIX_CLOCK_SELECTION 200809
_POSIX_CPUTIME 200809
_POSIX_THREAD_CPUTIME 200809
_POSIX_DEVICE_SPECIFIC
_POSIX_DEVICE_SPECIFIC_R
_POSIX_FD_MGMT
_POSIX_FIFO
_POSIX_PIPE
_POSIX_FILE_ATTRIBUTES
_POSIX_FILE_LOCKING
_POSIX_FILE_SYSTEM
_POSIX_MONOTONIC_CLOCK 200809
_POSIX_MULTI_PROCESS
_POSIX_SINGLE_PROCESS
_POSIX_NETWORKING
_POSIX_READER_WRITER_LOCKS 200809
_POSIX_SPIN_LOCKS 200809
_POSIX_REGEXP 1
_REGEX_VERSION
_POSIX_SHELL 1
_POSIX_SIGNALS
_POSIX_SPAWN 200809
_POSIX_SPORADIC_SERVER
_POSIX_THREAD_SPORADIC_SERVER
_POSIX_SYSTEM_DATABASE
_POSIX_SYSTEM_DATABASE_R
_POSIX_TIMEOUTS 200809
_POSIX_TYPED_MEMORY_OBJECTS
_POSIX_USER_GROUPS
_POSIX_USER_GROUPS_R
POSIX2_PBS
POSIX2_PBS_ACCOUNTING
POSIX2_PBS_LOCATE
POSIX2_PBS_TRACK
POSIX2_PBS_MESSAGE
SYMLOOP_MAX
STREAM_MAX 16
AIO_LISTIO_MAX
AIO_MAX
AIO_PRIO_DELTA_MAX 20
DELAYTIMER_MAX 2147483647
HOST_NAME_MAX 64
LOGIN_NAME_MAX 256
MQ_OPEN_MAX
MQ_PRIO_MAX 32768
_POSIX_DEVICE_IO
_POSIX_TRACE
_POSIX_TRACE_EVENT_FILTER
_POSIX_TRACE_INHERIT
_POSIX_TRACE_LOG
RTSIG_MAX 32
SEM_NSEMS_MAX
SEM_VALUE_MAX 2147483647
SIGQUEUE_MAX 127579
FILESIZEBITS 64
POSIX_ALLOC_SIZE_MIN 4096
POSIX_REC_INCR_XFER_SIZE
POSIX_REC_MAX_XFER_SIZE
POSIX_REC_MIN_XFER_SIZE 4096
POSIX_REC_XFER_ALIGN 4096
SYMLINK_MAX
GNU_LIBC_VERSION glibc 2.17
GNU_LIBPTHREAD_VERSION NPTL 2.17
POSIX2_SYMLINKS 1
LEVEL1_ICACHE_SIZE 32768
LEVEL1_ICACHE_ASSOC 8
LEVEL1_ICACHE_LINESIZE 64
LEVEL1_DCACHE_SIZE 32768
LEVEL1_DCACHE_ASSOC 8
LEVEL1_DCACHE_LINESIZE 64
LEVEL2_CACHE_SIZE 262144
LEVEL2_CACHE_ASSOC 8
LEVEL2_CACHE_LINESIZE 64
LEVEL3_CACHE_SIZE 6291456
LEVEL3_CACHE_ASSOC 12
LEVEL3_CACHE_LINESIZE 64
LEVEL4_CACHE_SIZE 0
LEVEL4_CACHE_ASSOC 0
LEVEL4_CACHE_LINESIZE 0
IPV6 200809
RAW_SOCKETS 200809
