System Interfaces: Table of Contents

• 1. Introduction
  • 1.1 Relationship to Other Formal Standards
  • 1.2 Format of Entries
• 2. General Information
  • 2.1 Use and Implementation of Interfaces
    • 2.1.1 Use and Implementation of Functions
    • 2.1.2 Use and Implementation of Macros
  • 2.2 The Compilation Environment
    • 2.2.1 POSIX.1 Symbols
      • 2.2.1.1 The _POSIX_C_SOURCE Feature Test Macro
      • 2.2.1.2 The _XOPEN_SOURCE Feature Test Macro
      • 2.2.1.3 The __STDC_WANT_LIB_EXT1__ Feature Test Macro
    • 2.2.2 The Name Space
  • 2.3 Error Numbers
    • 2.3.1 Additional Error Numbers
  • 2.4 Signal Concepts
    • 2.4.1 Signal Generation and Delivery
    • 2.4.2 Realtime Signal Generation and Delivery
    • 2.4.3 Signal Actions
      • SIG_DFL
      • SIG_IGN
      • Pointer to a Function
    • 2.4.4 Signal Effects on Other Functions
  • 2.5 Standard I/O Streams
    • 2.5.1 Interaction of File Descriptors and Standard I/O Streams
    • 2.5.2 Stream Orientation and Encoding Rules
  • 2.6 File Descriptor Allocation
  • 2.7 XSI Interprocess Communication
    • 2.7.1 IPC General Description
  • 2.8 Realtime
    • 2.8.1 Realtime Signals
    • 2.8.2 Asynchronous I/O
    • 2.8.3 Memory Management
      • 2.8.3.1 Memory Locking
      • 2.8.3.2 Memory Mapped Files
      • 2.8.3.3 Memory Protection
      • 2.8.3.4 Typed Memory Objects
    • 2.8.4 Process Scheduling
      • Scheduling Policies
      • SCHED_FIFO
      • SCHED_RR
      • SCHED_SPORADIC
      • SCHED_OTHER
    • 2.8.5 Clocks and Timers
      • Time Value Specification Structures
      • Timer Event Notification Control Block
      • Manifest Constants
      • Execution Time Monitoring
  • 2.9 Threads
    • 2.9.1 Thread-Safety
    • 2.9.2 Thread IDs
    • 2.9.3 Thread Mutexes
    • 2.9.4 Thread Scheduling
      • Thread Scheduling Attributes
      • Thread Scheduling Contention Scope
      • Scheduling Allocation Domain
      • Scheduling Documentation
    • 2.9.5 Thread Cancellation
      • 2.9.5.1 Cancelability States
      • 2.9.5.2 Cancellation Points
      • 2.9.5.3 Thread Cancellation Cleanup Handlers
      • 2.9.5.4 Async-Cancel Safety
    • 2.9.6 Thread Read-Write Locks
    • 2.9.7 Thread Interactions with File Operations
    • 2.9.8 Use of Application-Managed Thread Stacks
    • 2.9.9 Synchronization Object Copies and Alternative Mappings
  • 2.10 Sockets
    • 2.10.1 Address Families
    • 2.10.2 Addressing
    • 2.10.3 Protocols
    • 2.10.4 Routing
    • 2.10.5 Interfaces
    • 2.10.6 Socket Types
    • 2.10.7 Socket I/O Mode
    • 2.10.8 Socket Owner
    • 2.10.9 Socket Queue Limits
    • 2.10.10 Pending Error
    • 2.10.11 Socket Receive Queue
    • 2.10.12 Socket Out-of-Band Data State
    • 2.10.13 Connection Indication Queue
    • 2.10.14 Signals
    • 2.10.15 Asynchronous Errors
    • 2.10.16 Use of Options
    • 2.10.17 Use of Sockets for Local UNIX Connections
      • 2.10.17.1 Headers
    • 2.10.18 Use of Sockets over Internet Protocols
    • 2.10.19 Use of Sockets over Internet Protocols Based on IPv4
      • 2.10.19.1 Headers
    • 2.10.20 Use of Sockets over Internet Protocols Based on IPv6
      • 2.10.20.1 Addressing
      • 2.10.20.2 Compatibility with IPv4
      • 2.10.20.3 Interface Identification
      • 2.10.20.4 Options
      • 2.10.20.5 Headers
  • 2.11 Data Types
    • 2.11.1 Defined Types
    • 2.11.2 The char Type
  • 2.12 Status Information
    • Footnotes
• 3. System Interfaces
  • CMPLX
  • _Exit
  • a64l
  • abort
  • abs
  • accept
  • access
  • acos
  • acosh
  • aio_cancel
  • aio_error
  • aio_fsync
  • aio_read
  • aio_return
  • aio_suspend
  • aio_write
  • alarm
  • aligned_alloc
  • alphasort
  • asctime
  • asin
  • asinh
  • assert
  • at_quick_exit
  • atan
  • atan2
  • atanh
  • atexit
  • atof
  • atoi
  • atol
  • atomic_compare_exchange_strong
  • atomic_exchange
  • atomic_fetch_add
  • atomic_flag_clear
  • atomic_flag_test_and_set
  • atomic_init
  • atomic_is_lock_free
  • atomic_load
  • atomic_signal_fence
  • atomic_store
  • basename
  • be16toh
  • bind
  • bindtextdomain
  • bsearch
  • btowc
  • c16rtomb
  • cabs
  • cacos
  • cacosh
  • call_once
  • calloc
  • carg
  • casin
  • casinh
  • catan
  • catanh
  • catclose
  • catgets
  • catopen
  • cbrt
  • ccos
  • ccosh
  • ceil
  • cexp
  • cfgetispeed
  • cfgetospeed
  • cfsetispeed
  • cfsetospeed
  • chdir
  • chmod
  • chown
  • cimag
  • clearerr
  • clock
  • clock_getcpuclockid
  • clock_getres
  • clock_nanosleep
  • clog
  • close
  • closedir
  • closelog
  • cnd_broadcast
  • cnd_destroy
  • cnd_timedwait
  • confstr
  • conj
  • connect
  • copysign
  • cos
  • cosh
  • cpow
  • cproj
  • creal
  • creat
  • crypt
  • csin
  • csinh
  • csqrt
  • ctan
  • ctanh
  • ctermid
  • ctime
  • dbm_clearerr
  • difftime
  • dirfd
  • dirname
  • div
  • dladdr
  • dlclose
  • dlerror
  • dlopen
  • dlsym
  • drand48
  • dup
  • duplocale
  • encrypt
  • endgrent
  • endhostent
  • endnetent
  • endprotoent
  • endpwent
  • endservent
  • endutxent
  • erf
  • erfc
  • errno
  • exec
  • exit
  • exp
  • exp2
  • expm1
  • fabs
  • fchdir
  • fchmod
  • fchown
  • fclose
  • fcntl
  • fdatasync
  • fdim
  • fdopen
  • fdopendir
  • feclearexcept
  • fegetenv
  • fegetexceptflag
  • fegetround
  • feholdexcept
  • feof
  • feraiseexcept
  • ferror
  • fetestexcept
  • feupdateenv
  • fflush
  • ffs
  • fgetc
  • fgetpos
  • fgets
  • fgetwc
  • fgetws
  • fileno
  • flockfile
  • floor
  • fma
  • fmax
  • fmemopen
  • fmin
  • fmod
  • fmtmsg
  • fnmatch
  • fopen
  • fork
  • fpathconf
  • fpclassify
  • fprintf
  • fputc
  • fputs
  • fputwc
  • fputws
  • fread
  • free
  • freeaddrinfo
  • freelocale
  • freopen
  • frexp
  • fscanf
  • fseek
  • fsetpos
  • fstat
  • fstatat
  • fstatvfs
  • fsync
  • ftell
  • ftok
  • ftruncate
  • futimens
  • fwide
  • fwprintf
  • fwrite
  • fwscanf
  • gai_strerror
  • getc
  • getc_unlocked
  • getchar
  • getcwd
  • getdate
  • getdelim
  • getegid
  • getentropy
  • getenv
  • geteuid
  • getgid
  • getgrgid
  • getgrnam
  • getgroups
  • gethostid
  • gethostname
  • getlocalename_l
  • getlogin
  • getnameinfo
  • getopt
  • getpeername
  • getpgid
  • getpgrp
  • getpid
  • getppid
  • getpriority
  • getpwnam
  • getpwuid
  • getresgid
  • getresuid
  • getrlimit
  • getrusage
  • getsid
  • getsockname
  • getsockopt
  • getsubopt
  • gettext
  • getuid
  • getwc
  • getwchar
  • glob
  • gmtime
  • grantpt
  • hcreate
  • htonl
  • hypot
  • iconv
  • iconv_close
  • iconv_open
  • if_freenameindex
  • if_indextoname
  • if_nameindex
  • if_nametoindex
  • ilogb
  • imaxabs
  • imaxdiv
  • in6addr_any
  • inet_addr
  • inet_ntop
  • initstate
  • insque
  • isalnum
  • isalpha
  • isatty
  • isblank
  • iscntrl
  • isdigit
  • isfinite
  • isgraph
  • isgreater
  • isinf
  • islower
  • isnan
  • isnormal
  • isprint
  • ispunct
  • isspace
  • isunordered
  • isupper
  • iswalnum
  • iswalpha
  • iswblank
  • iswcntrl
  • iswctype
  • iswdigit
  • iswgraph
  • iswlower
  • iswprint
  • iswpunct
  • iswspace
  • iswupper
  • iswxdigit
  • isxdigit
  • j0
  • kill
  • kill_dependency
  • killpg
  • labs
  • lchown
  • ldexp
  • ldiv
  • lgamma
  • link
  • lio_listio
  • listen
  • llrint
  • llround
  • localeconv
  • localtime
  • lockf
  • log
  • log10
  • log1p
  • log2
  • logb
  • longjmp
  • lrint
  • lround
  • lsearch
  • lseek
  • malloc
  • mblen
  • mbrlen
  • mbrtoc16
  • mbrtowc
  • mbsinit
  • mbsrtowcs
  • mbstowcs
  • mbtowc
  • memccpy
  • memchr
  • memcmp
  • memcpy
  • memmem
  • memmove
  • memset
  • mkdir
  • mkdtemp
  • mkfifo
  • mknod
  • mktime
  • mlock
  • mlockall
  • mmap
  • modf
  • mprotect
  • mq_close
  • mq_getattr
  • mq_notify
  • mq_open
  • mq_receive
  • mq_send
  • mq_setattr
  • mq_unlink
  • msgctl
  • msgget
  • msgrcv
  • msgsnd
  • msync
  • mtx_destroy
  • mtx_lock
  • munmap
  • nan
  • nanosleep
  • nearbyint
  • newlocale
  • nextafter
  • nftw
  • nice
  • nl_langinfo
  • open
  • open_memstream
  • pause
  • pclose
  • perror
  • pipe
  • poll
  • popen
  • posix_devctl
  • posix_fadvise
  • posix_fallocate
  • posix_getdents
  • posix_madvise
  • posix_mem_offset
  • posix_memalign
  • posix_openpt
  • posix_spawn
  • posix_spawn_file_actions_addchdir
  • posix_spawn_file_actions_addclose
  • posix_spawn_file_actions_adddup2
  • posix_spawn_file_actions_destroy
  • posix_spawnattr_destroy
  • posix_spawnattr_getflags
  • posix_spawnattr_getpgroup
  • posix_spawnattr_getschedparam
  • posix_spawnattr_getschedpolicy
  • posix_spawnattr_getsigdefault
  • posix_spawnattr_getsigmask
  • posix_typed_mem_get_info
  • posix_typed_mem_open
  • pow
  • pselect
  • psiginfo
  • pthread_atfork
  • pthread_attr_destroy
  • pthread_attr_getdetachstate
  • pthread_attr_getguardsize
  • pthread_attr_getinheritsched
  • pthread_attr_getschedparam
  • pthread_attr_getschedpolicy
  • pthread_attr_getscope
  • pthread_attr_getstack
  • pthread_attr_getstacksize
  • pthread_barrier_destroy
  • pthread_barrier_wait
  • pthread_barrierattr_destroy
  • pthread_barrierattr_getpshared
  • pthread_cancel
  • pthread_cleanup_pop
  • pthread_cond_broadcast
  • pthread_cond_clockwait
  • pthread_cond_destroy
  • pthread_condattr_destroy
  • pthread_condattr_getclock
  • pthread_condattr_getpshared
  • pthread_create
  • pthread_detach
  • pthread_equal
  • pthread_exit
  • pthread_getcpuclockid
  • pthread_getschedparam
  • pthread_getspecific
  • pthread_join
  • pthread_key_create
  • pthread_key_delete
  • pthread_kill
  • pthread_mutex_clocklock
  • pthread_mutex_consistent
  • pthread_mutex_destroy
  • pthread_mutex_getprioceiling
  • pthread_mutex_lock
  • pthread_mutexattr_destroy
  • pthread_mutexattr_getprioceiling
  • pthread_mutexattr_getprotocol
  • pthread_mutexattr_getpshared
  • pthread_mutexattr_getrobust
  • pthread_mutexattr_gettype
  • pthread_once
  • pthread_rwlock_clockrdlock
  • pthread_rwlock_clockwrlock
  • pthread_rwlock_destroy
  • pthread_rwlock_rdlock
  • pthread_rwlock_trywrlock
  • pthread_rwlock_unlock
  • pthread_rwlockattr_destroy
  • pthread_rwlockattr_getpshared
  • pthread_self
  • pthread_setcancelstate
  • pthread_setschedprio
  • pthread_sigmask
  • pthread_spin_destroy
  • pthread_spin_lock
  • pthread_spin_unlock
  • ptsname
  • putc
  • putchar
  • putenv
  • puts
  • putwc
  • putwchar
  • qsort
  • quick_exit
  • raise
  • rand
  • read
  • readdir
  • readlink
  • readv
  • realloc
  • realpath
  • recv
  • recvfrom
  • recvmsg
  • regcomp
  • remainder
  • remove
  • remquo
  • rename
  • rewind
  • rewinddir
  • rint
  • rmdir
  • round
  • scalbln
  • sched_get_priority_max
  • sched_getparam
  • sched_getscheduler
  • sched_rr_get_interval
  • sched_setparam
  • sched_setscheduler
  • sched_yield
  • seekdir
  • sem_clockwait
  • sem_close
  • sem_destroy
  • sem_getvalue
  • sem_init
  • sem_open
  • sem_post
  • sem_trywait
  • sem_unlink
  • semctl
  • semget
  • semop
  • send
  • sendmsg
  • sendto
  • setbuf
  • setegid
  • setenv
  • seteuid
  • setgid
  • setjmp
  • setkey
  • setlocale
  • setpgid
  • setregid
  • setresgid
  • setresuid
  • setreuid
  • setsid
  • setsockopt
  • setuid
  • setvbuf
  • shm_open
  • shm_unlink
  • shmat
  • shmctl
  • shmdt
  • shmget
  • shutdown
  • sig2str
  • sigaction
  • sigaddset
  • sigaltstack
  • sigdelset
  • sigemptyset
  • sigfillset
  • sigismember
  • siglongjmp
  • signal
  • signbit
  • sigpending
  • sigqueue
  • sigsetjmp
  • sigsuspend
  • sigtimedwait
  • sigwait
  • sin
  • sinh
  • sleep
  • sockatmark
  • socket
  • socketpair
  • sqrt
  • stdin
  • strcasecmp
  • strcat
  • strchr
  • strcmp
  • strcoll
  • strcpy
  • strcspn
  • strdup
  • strerror
  • strfmon
  • strftime
  • strlcat
  • strlen
  • strncat
  • strncmp
  • strncpy
  • strpbrk
  • strptime
  • strrchr
  • strsignal
  • strspn
  • strstr
  • strtod
  • strtoimax
  • strtok
  • strtol
  • strtoul
  • strxfrm
  • swab
  • symlink
  • sync
  • sysconf
  • system
  • tan
  • tanh
  • tcdrain
  • tcflow
  • tcflush
  • tcgetattr
  • tcgetpgrp
  • tcgetsid
  • tcgetwinsize
  • tcsendbreak
  • tcsetattr
  • tcsetpgrp
  • tcsetwinsize
  • tdelete
  • telldir
  • tgamma
  • thrd_create
  • thrd_current
  • thrd_detach
  • thrd_equal
  • thrd_exit
  • thrd_join
  • thrd_sleep
  • thrd_yield
  • time
  • timer_create
  • timer_delete
  • timer_getoverrun
  • times
  • timespec_get
  • tmpfile
  • tmpnam
  • tolower
  • toupper
  • towctrans
  • towlower
  • towupper
  • trunc
  • truncate
  • tss_create
  • tss_delete
  • tss_get
  • ttyname
  • tzset
  • umask
  • uname
  • ungetc
  • ungetwc
  • unlink
  • unlockpt
  • unsetenv
  • uselocale
  • vfprintf
  • vfscanf
  • vfwprintf
  • vfwscanf
  • wait
  • waitid
  • wcrtomb
  • wcscasecmp
  • wcscat
  • wcschr
  • wcscmp
  • wcscoll
  • wcscpy
  • wcscspn
  • wcsdup
  • wcsftime
  • wcslcat
  • wcslen
  • wcsncat
  • wcsncmp
  • wcsncpy
  • wcspbrk
  • wcsrchr
  • wcsrtombs
  • wcsspn
  • wcsstr
  • wcstod
  • wcstoimax
  • wcstok
  • wcstol
  • wcstombs
  • wcstoul
  • wcswidth
  • wcsxfrm
  • wctob
  • wctomb
  • wctrans
  • wctype
  • wcwidth
  • wmemchr
  • wmemcmp
  • wmemcpy
  • wmemmove
  • wmemset
  • wordexp
  • write
  • writev
  • y0