A

• a64l(3)convert between long and base-64
• abort(3)cause abnormal process termination
• abs(3)compute the absolute value of an integer
• acos(3)arc cosine function
• acosh(3)inverse hyperbolic cosine function
• addseverity(3)introduce new severity classes
• adjtime(3)correct the time to synchronize the system clock
• aio_cancel(3)cancel an outstanding asynchronous I/O request
• aio_error(3)get error status of asynchronous I/O operation
• aio_fsync(3)asynchronous file synchronization
• aio_init(3)asynchronous I/O initialization
• aio_read(3)asynchronous read
• aio_return(3)get return status of asynchronous I/O operation
• aio_suspend(3)wait for asynchronous I/O operation or timeout
• aio_write(3)asynchronous write
• aiocb(3)asynchronous I/O control block
• alloca(3)allocate memory that is automatically freed
• arc4random(3)cryptographically-secure pseudorandom number generator
• argz_add(3)functions to handle an argz list
• asin(3)arc sine function
• asinh(3)inverse hyperbolic sine function
• asprintf(3)print to allocated string
• assert(3)abort the program if assertion is false
• assert_perror(3)test errnum and abort
• atan(3)arc tangent function
• atan2(3)arc tangent function of two variables
• atanh(3)inverse hyperbolic tangent function
• atexit(3)register a function to be called at normal process termination
• atof(3)convert a string to a double
• atoi(3)convert a string to an integer

B

• backtrace(3)support for application self-debugging
• basename(3)parse pathname components
• bcmp(3)compare byte sequences
• bcopy(3)copy byte sequence
• bindresvport(3)bind a socket to a privileged IP port
• blkcnt_t(3)file block counts
• blksize_t(3)file block sizes
• bsd_signal(3)signal handling with BSD semantics
• bsearch(3)binary search of a sorted array
• bstring(3)byte string operations
• bswap(3)reverse order of bytes
• btowc(3)convert single byte to wide character
• btree(3)btree database access method
• byteorder(3)convert values between host and network byte order
• bzero(3)zero a byte string

C

• cabs(3)absolute value of a complex number
• cacos(3)complex arc cosine
• cacosh(3)complex arc hyperbolic cosine
• canonicalize_file_name(3)return the canonicalized absolute pathname
• carg(3)calculate the complex argument
• casin(3)complex arc sine
• casinh(3)complex arc sine hyperbolic
• catan(3)complex arc tangents
• catanh(3)complex arc tangents hyperbolic
• catgets(3)get message from a message catalog
• catopen(3)open/close a message catalog
• cbrt(3)cube root function
• cc_t(3)terminal special characters, baud rates, modes
• ccos(3)complex cosine function
• ccosh(3)complex hyperbolic cosine
• ceil(3)ceiling function: smallest integral value not less than argument
• cexp(3)complex exponential function
• cexp2(3)base-2 exponent of a complex number
• cfree(3)free allocated memory
• cimag(3)get imaginary part of a complex number
• circleq(3)implementation of a doubly linked circular queue
• clearenv(3)clear the environment
• clock(3)determine processor time
• clock_getcpuclockid(3)obtain ID of a process CPU-time clock
• clock_t(3)system time
• clockid_t(3)clock ID for the clock and timer functions
• clog(3)natural logarithm of a complex number
• clog10(3)base-10 logarithm of a complex number
• clog2(3)base-2 logarithm of a complex number
• closedir(3)close a directory
• cmsg(3)access ancillary data
• confstr(3)get configuration dependent string variables
• conj(3)calculate the complex conjugate
• copysign(3)copy sign of a number
• cos(3)cosine function
• cosh(3)hyperbolic cosine function
• cpow(3)complex power function
• cproj(3)project into Riemann Sphere
• CPU_SET(3)macros for manipulating CPU sets
• creal(3)get real part of a complex number
• csin(3)complex sine function
• csinh(3)complex hyperbolic sine
• csqrt(3)complex square root
• ctan(3)complex tangent function
• ctanh(3)complex hyperbolic tangent
• ctermid(3)get controlling terminal name
• ctime(3)transform date and time to broken-down time or ASCII

D

• daemon(3)run in the background
• dbopen(3)database access methods
• des_crypt(3)fast DES encryption
• dev_t(3)device ID
• difftime(3)calculate time difference
• dirfd(3)get directory stream file descriptor
• div(3)compute quotient and remainder of an integer division
• div_t(3)quotient and remainder of an integer division
• dl_iterate_phdr(3)walk through list of shared objects
• dladdr(3)translate address to symbolic information
• dlerror(3)obtain error diagnostic for functions in the dlopen API
• dlinfo(3)obtain information about a dynamically loaded object
• dlopen(3)open and close a shared object
• dlsym(3)obtain address of a symbol in a shared object or executable
• double_t(3)most efficient floating types
• drand48(3)generate uniformly distributed pseudo-random numbers
• drand48_r(3)generate uniformly distributed pseudo-random numbers reentrantly
• duplocale(3)duplicate a locale object
• dysize(3)get number of days for a given year

E

• ecvt(3)convert a floating-point number to a string
• ecvt_r(3)convert a floating-point number to a string
• encrypt(3)encrypt 64-bit messages
• end(3)end of program segments
• endian(3)convert values between host and big-/little-endian byte order
• envz_add(3)environment string support
• EOF(3)end of file or error indicator
• epoll_event(3)epoll event
• erf(3)error function
• erfc(3)complementary error function
• err(3)formatted error messages
• errno(3)number of last error
• error(3)glibc error reporting functions
• ether_aton(3)Ethernet address manipulation routines
• euidaccess(3)check effective user's permissions for a file
• exec(3)execute a file
• exit(3)cause normal process termination
• EXIT_SUCCESS(3)termination status constants
• exp(3)base-e exponential function
• exp10(3)base-10 exponential function
• exp2(3)base-2 exponential function
• expm1(3)exponential minus 1

F

• fabs(3)absolute value of floating-point number
• fclose(3)close a stream
• fcloseall(3)close all open streams
• fdim(3)positive difference
• fenv(3)floating-point rounding and exception handling
• fenv_t(3)floating-point environment
• ferror(3)check and reset stream status
• fexecve(3)execute program specified via file descriptor
• fflush(3)flush a stream
• ffs(3)find first bit set in a word
• fgetc(3)input of characters and strings
• fgetgrent(3)get group file entry
• fgetpwent(3)get password file entry
• fgetwc(3)read a wide character from a FILE stream
• fgetws(3)read a wide-character string from a FILE stream
• FILE(3)input/output stream
• filefuncs(3)provide some file related functionality to gawk
• fileno(3)obtain file descriptor of a stdio stream
• finite(3)BSD floating-point classification functions
• flockfile(3)lock FILE for stdio
• floor(3)largest integral value not greater than argument
• fma(3)floating-point multiply and add
• fmax(3)determine maximum of two floating-point numbers
• fmemopen(3)open memory as stream
• fmin(3)determine minimum of two floating-point numbers
• fmod(3)floating-point remainder function
• fmtmsg(3)print formatted error messages
• fnmatch(3)match filename or pathname
• fopen(3)stream open functions
• fopencookie(3)open a custom stream
• fork(3)basic process management
• fpathconf(3)get configuration values for files
• fpclassify(3)floating-point classification macros
• fpurge(3)purge a stream
• fputwc(3)write a wide character to a FILE stream
• fputws(3)write a wide-character string to a FILE stream
• fread(3)binary stream input/output
• frexp(3)convert floating-point number to fractional and integral components
• fseek(3)reposition a stream
• fseeko(3)seek to or report file position
• ftime(3)return date and time
• ftok(3)convert a pathname and a project identifier to a System V IPC key
• fts(3)traverse a file hierarchy
• ftw(3)file tree walk
• futimes(3)change file timestamps
• fwide(3)set and determine the orientation of a FILE stream

G

• gamma(3)(logarithm of the) gamma function
• gcvt(3)convert a floating-point number to a string
• get_nprocs(3)get number of processors
• get_phys_pages(3)get total and available physical page counts
• getaddrinfo(3)network address and service translation
• getaddrinfo_a(3)asynchronous network address and service translation
• getauxval(3)retrieve a value from the auxiliary vector
• getcontext(3)get or set the user context
• getcwd(3)get current working directory
• getdate(3)convert a date-plus-time string to broken-down time
• getdirentries(3)get directory entries in a filesystem-independent format
• getdtablesize(3)get file descriptor table size
• getentropy(3)fill a buffer with random bytes
• getenv(3)get an environment variable
• getfsent(3)handle fstab entries
• getgrent(3)get group file entry
• getgrent_r(3)get group file entry reentrantly
• getgrnam(3)get group file entry
• getgrouplist(3)get list of groups to which a user belongs
• gethostbyname(3)get network host entry
• gethostid(3)get or set the unique identifier of the current host
• getifaddrs(3)get interface addresses
• getipnodebyname(3)get network hostnames and addresses
• getline(3)delimited string input
• getloadavg(3)get system load averages
• getlogin(3)get username
• getmntent(3)get filesystem descriptor file entry
• getnameinfo(3)address-to-name translation in protocol-independent manner
• getnetent(3)get network entry
• getnetent_r(3)get network entry (reentrant)
• getopt(3)Parse command-line options
• getpass(3)get a password
• getprotoent(3)get protocol entry
• getprotoent_r(3)get protocol entry (reentrant)
• getpt(3)open a new pseudoterminal master
• getpw(3)reconstruct password line entry
• getpwent(3)get password file entry
• getpwent_r(3)get passwd file entry reentrantly
• getpwnam(3)get password file entry
• getrpcent(3)get RPC entry
• getrpcent_r(3)get RPC entry (reentrant)
• getrpcport(3)get RPC port number
• gets(3)get a string from standard input (DEPRECATED)
• getservent(3)get service entry
• getservent_r(3)get service entry (reentrant)
• getspnam(3)get shadow password file entry
• getsubopt(3)parse suboption arguments from a string
• getttyent(3)get ttys file entry
• getusershell(3)get permitted user shells
• getutent(3)access utmp file entries
• getutmp(3)copy utmp structure to utmpx, and vice versa
• getw(3)input and output of words (ints)
• getwchar(3)read a wide character from standard input
• Git(3)Perl interface to the Git version control system
• glob(3)find pathnames matching a pattern, free memory from glob()
• gnu_get_libc_version(3)get glibc version and release
• grantpt(3)grant access to the slave pseudoterminal
• group_member(3)test whether a process is in a group
• gsignal(3)software signal facility

H

• hash(3)hash database access method
• hsearch(3)hash table management
• hypot(3)Euclidean distance function

I

• iconv(3)perform character set conversion
• iconv_close(3)deallocate descriptor for character set conversion
• iconv_open(3)allocate descriptor for character set conversion
• id_t(3)process/user/group identifier
• if_nameindex(3)get network interface names and indexes
• if_nametoindex(3)mappings between network interface names and indexes
• ilogb(3)get integer exponent of a floating-point value
• index(3)locate character in string
• inet(3)Internet address manipulation routines
• inet_net_pton(3)Internet network number conversion
• inet_ntop(3)convert IPv4 and IPv6 addresses from binary to text form
• inet_pton(3)convert IPv4 and IPv6 addresses from text to binary form
• INFINITY(3)floating-point constants
• initgroups(3)initialize the supplementary group access list
• inplace(3)emulate sed/perl/ruby in-place editing
• insque(3)insert/remove an item from a queue
• intmax_t(3)greatest-width basic integer types
• intN_t(3)fixed-width basic integer types
• intptr_t(3)integer types wide enough to hold pointers
• intro(3)introduction to library functions
• iovec(3)Vector I/O data structure
• isalpha(3)character classification functions
• isatty(3)test whether a file descriptor refers to a terminal
• isfdtype(3)test file type of a file descriptor
• isgreater(3)floating-point relational tests without exception for NaN
• iswalnum(3)test for alphanumeric wide character
• iswalpha(3)test for alphabetic wide character
• iswblank(3)test for whitespace wide character
• iswcntrl(3)test for control wide character
• iswctype(3)wide-character classification
• iswdigit(3)test for decimal digit wide character
• iswgraph(3)test for graphic wide character
• iswlower(3)test for lowercase wide character
• iswprint(3)test for printing wide character
• iswpunct(3)test for punctuation or symbolic wide character
• iswspace(3)test for whitespace wide character
• iswupper(3)test for uppercase wide character
• iswxdigit(3)test for hexadecimal digit wide character
• itimerspec(3)interval for a timer with nanosecond precision

J

• j0(3)Bessel functions of the first kind

K

• key_setsecret(3)interfaces to rpc keyserver daemon
• killpg(3)send signal to a process group

L

• lconv(3)numeric formatting information
• ldexp(3)multiply floating-point number by integral power of 2
• lgamma(3)log gamma function
• libnetlink(3)A library for accessing the netlink service
• lio_listio(3)initiate a list of I/O requests
• list(3)implementation of a doubly linked list
• localeconv(3)get numeric formatting information
• lockf(3)apply, test or remove a POSIX lock on an open file
• log(3)natural logarithmic function
• log10(3)base-10 logarithmic function
• log1p(3)logarithm of 1 plus argument
• log2(3)base-2 logarithmic function
• logb(3)get exponent of a floating-point value
• login(3)write utmp and wtmp entries
• lrint(3)round to nearest integer
• lround(3)round to nearest integer
• lsearch(3)linear search of an array
• lseek64(3)reposition 64-bit read/write file offset

M

• makecontext(3)manipulate user context
• makedev(3)manage a device number
• mallinfo(3)obtain memory allocation information
• malloc(3)allocate and free dynamic memory
• malloc_get_state(3)record and restore state of malloc implementation
• malloc_hook(3)malloc debugging variables (DEPRECATED)
• malloc_info(3)export malloc state to a stream
• malloc_stats(3)print memory allocation statistics
• malloc_trim(3)release free memory from the heap
• malloc_usable_size(3)obtain size of block of memory allocated from heap
• mallopt(3)set memory allocation parameters
• matherr(3)SVID math library exception handling
• MAX(3)maximum or minimum of two values
• MB_CUR_MAX(3)maximum length of a multibyte character in the current locale
• MB_LEN_MAX(3)maximum multibyte length of a character across all locales
• mblen(3)determine number of bytes in next multibyte character
• mbrlen(3)determine number of bytes in next multibyte character
• mbrtowc(3)convert a multibyte sequence to a wide character
• mbsinit(3)test for initial shift state
• mbsnrtowcs(3)convert a multibyte string to a wide-character string
• mbsrtowcs(3)convert a multibyte string to a wide-character string (restartable)
• mbstowcs(3)convert a multibyte string to a wide-character string
• mbtowc(3)convert a multibyte sequence to a wide character
• mcheck(3)heap consistency checking
• memccpy(3)copy memory area
• memchr(3)scan memory for a character
• memcmp(3)compare memory areas
• memcpy(3)copy memory area
• memfrob(3)frobnicate (obfuscate) a memory area
• memmem(3)locate a substring
• memmove(3)copy memory area
• mempcpy(3)copy memory area
• memset(3)fill memory with a constant byte
• mkdtemp(3)create a unique temporary directory
• mkfifo(3)make a FIFO special file (a named pipe)
• mkstemp(3)create a unique temporary file
• mktemp(3)make a unique temporary filename
• mode_t(3)file attributes
• modf(3)extract signed integral and fractional values from floating-point number
• mpool(3)shared memory buffer pool
• mq_close(3)close a message queue descriptor
• mq_getattr(3)get/set message queue attributes
• mq_notify(3)register for notification when a message is available
• mq_open(3)open a message queue
• mq_receive(3)receive a message from a message queue
• mq_send(3)send a message to a message queue
• mq_unlink(3)remove a message queue
• mtrace(3)malloc tracing

N

• nan(3)return 'Not a Number'
• netlink(3)Netlink macros
• newlocale(3)create, modify, and free a locale object
• nextafter(3)floating-point number manipulation
• nextup(3)return next floating-point number toward positive/negative infinity
• nl_langinfo(3)query language and locale information
• ntp_gettime(3)get time parameters (NTP daemon interface)
• NULL(3)null pointer constant

O

• off_t(3)file sizes
• offsetof(3)offset of a structure member
• on_exit(3)register a function to be called at normal process termination
• open_memstream(3)open a dynamic memory buffer stream
• opendir(3)open a directory
• openpty(3)terminal utility functions
• ordchr(3)convert characters to strings and vice versa

P

• perror(3)print a system error message
• popen(3)pipe stream to or from a process
• posix_fallocate(3)allocate file space
• posix_madvise(3)give advice about patterns of memory usage
• posix_memalign(3)allocate aligned memory
• posix_openpt(3)open a pseudoterminal device
• posix_spawn(3)spawn a process
• pow(3)power functions
• pow10(3)base-10 power functions
• powerof2(3)test if a value is a power of 2
• printf(3)formatted output conversion
• printf.h(3)define custom behavior for printf-like functions
• procps(3)API to access system level information in the /proc filesystem
• procps_misc(3)API for miscellaneous information in the /proc filesystem
• procps_pids(3)API to access process information in the /proc filesystem
• profil(3)execution time profile
• program_invocation_name(3)obtain name used to invoke calling program
• psignal(3)print signal description
• pthread_attr_init(3)initialize and destroy thread attributes object
• pthread_attr_setaffinity_np(3)set/get CPU affinity attribute in thread attributes object
• pthread_attr_setdetachstate(3)set/get detach state attribute in thread attributes object
• pthread_attr_setguardsize(3)set/get guard size attribute in thread attributes object
• pthread_attr_setinheritsched(3)set/get inherit-scheduler attribute in thread attributes object
• pthread_attr_setschedparam(3)set/get scheduling parameter attributes in thread attributes object
• pthread_attr_setschedpolicy(3)set/get scheduling policy attribute in thread attributes object
• pthread_attr_setscope(3)set/get contention scope attribute in thread attributes object
• pthread_attr_setsigmask_np(3)set/get signal mask attribute in thread attributes object
• pthread_attr_setstack(3)set/get stack attributes in thread attributes object
• pthread_attr_setstackaddr(3)set/get stack address attribute in thread attributes object
• pthread_attr_setstacksize(3)set/get stack size attribute in thread attributes object
• pthread_cancel(3)send a cancelation request to a thread
• pthread_cleanup_push(3)push and pop thread cancelation clean-up handlers
• pthread_cleanup_push_defer_np(3)push and pop thread cancelation clean-up handlers while saving cancelability type
• pthread_create(3)create a new thread
• pthread_detach(3)detach a thread
• pthread_equal(3)compare thread IDs
• pthread_exit(3)terminate calling thread
• pthread_getattr_default_np(3)get or set default thread-creation attributes
• pthread_getattr_np(3)get attributes of created thread
• pthread_getcpuclockid(3)retrieve ID of a thread's CPU time clock
• pthread_join(3)join with a terminated thread
• pthread_kill(3)send a signal to a thread
• pthread_kill_other_threads_np(3)terminate all other threads in process
• pthread_mutex_consistent(3)make a robust mutex consistent
• pthread_mutexattr_getpshared(3)get/set process-shared mutex attribute
• pthread_mutexattr_setrobust(3)get and set the robustness attribute of a mutex attributes object
• pthread_rwlockattr_setkind_np(3)set/get the read-write lock kind of the thread read-write lock attribute object
• pthread_self(3)obtain ID of the calling thread
• pthread_setaffinity_np(3)set/get CPU affinity of a thread
• pthread_setcancelstate(3)set cancelability state and type
• pthread_setconcurrency(3)set/get the concurrency level
• pthread_setname_np(3)set/get the name of a thread
• pthread_setschedparam(3)set/get scheduling policy and parameters of a thread
• pthread_setschedprio(3)set scheduling priority of a thread
• pthread_sigmask(3)examine and change mask of blocked signals
• pthread_sigqueue(3)queue a signal and data to a thread
• pthread_spin_init(3)initialize or destroy a spin lock
• pthread_spin_lock(3)lock and unlock a spin lock
• pthread_testcancel(3)request delivery of any pending cancelation request
• pthread_tryjoin_np(3)try to join with a terminated thread
• pthread_yield(3)yield the processor
• ptrdiff_t(3)count of elements or array index
• ptsname(3)get the name of the slave pseudoterminal
• putenv(3)change or add an environment variable
• putgrent(3)write a group database entry to a file
• putpwent(3)write a password file entry
• puts(3)output of characters and strings
• putwchar(3)write a wide character to standard output

Q

• qecvt(3)convert a floating-point number to a string
• qsort(3)sort an array

R

• raise(3)send a signal to the caller
• rand(3)pseudo-random number generator
• random(3)random number generator
• random_r(3)reentrant random number generator
• rcmd(3)routines for returning a stream to a remote command
• re_comp(3)BSD regex functions
• readdir(3)read a directory
• readdir_r(3)read a directory
• readfile(3)return the entire contents of a file as a string
• realpath(3)return the canonicalized absolute pathname
• recno(3)record number database access method
• regex(3)POSIX regex functions
• remainder(3)floating-point remainder function
• remove(3)remove a file or directory
• remquo(3)remainder and part of quotient
• resolver(3)resolver routines
• revoutput(3)Reverse output strings sample extension
• revtwoway(3)Reverse strings sample two-way processor extension
• rewinddir(3)reset directory stream
• rexec(3)return stream to a remote command
• rint(3)round to nearest integer
• round(3)round to nearest integer, away from zero
• roundup(3)round up in steps
• rpc(3)library routines for remote procedure calls
• rpmatch(3)determine if the answer to a question is affirmative or negative
• rtime(3)get time from a remote machine
• rtnetlink(3)macros to manipulate rtnetlink messages
• rwarray(3)write and read gawk arrays to/from files

S

• scalb(3)multiply floating-point number by integral power of radix (OBSOLETE)
• scalbln(3)multiply floating-point number by integral power of radix
• scandir(3)scan a directory for matching entries
• scanf(3)input FILE format conversion
• sched_getcpu(3)determine CPU on which the calling thread is running
• seekdir(3)set the position of the next readdir() call in the directory stream.
• sem_close(3)close a named semaphore
• sem_destroy(3)destroy an unnamed semaphore
• sem_getvalue(3)get the value of a semaphore
• sem_init(3)initialize an unnamed semaphore
• sem_open(3)initialize and open a named semaphore
• sem_post(3)unlock a semaphore
• sem_unlink(3)remove a named semaphore
• sem_wait(3)lock a semaphore
• setaliasent(3)read an alias entry
• setbuf(3)stream buffering operations
• setenv(3)change or add an environment variable
• setjmp(3)performing a nonlocal goto
• setlocale(3)set the current locale
• setlogmask(3)set log priority mask
• setnetgrent(3)handle network group entries
• shm_open(3)create/open or unlink POSIX shared memory objects
• sigevent(3)structure for notification from asynchronous routines
• siginterrupt(3)allow signals to interrupt system calls
• signbit(3)test sign of a real floating-point number
• significand(3)get mantissa of floating-point number
• sigpause(3)atomically release blocked signals and wait for interrupt
• sigqueue(3)queue a signal and data to a process
• sigset(3)System V signal API
• sigsetops(3)POSIX signal set operations
• sigvec(3)BSD signal API
• sigwait(3)wait for a signal
• sin(3)sine function
• sincos(3)calculate sin and cos simultaneously
• sinh(3)hyperbolic sine function
• size_t(3)count of bytes
• sleep(3)sleep for a specified number of seconds
• slist(3)implementation of a singly linked list
• sockaddr(3)socket address
• sockatmark(3)determine whether socket is at out-of-band mark
• sqrt(3)square root function
• sscanf(3)input string format conversion
• stailq(3)implementation of a singly linked tail queue
• stat(3)file status
• static_assert(3)fail compilation if assertion is false
• statvfs(3)get filesystem statistics
• stdarg(3)variable argument lists
• stdin(3)standard I/O streams
• stdio(3)standard input/output library functions
• stdio_ext(3)interfaces to stdio FILE structure
• stpncpy(3)fill a fixed-size buffer with non-null bytes from a string, padding with null bytes as needed
• strcasecmp(3)compare two strings ignoring case
• strchr(3)locate character in string
• strcmp(3)compare two strings
• strcoll(3)compare two strings using the current locale
• strcpy(3)copy or catenate a string
• strdup(3)duplicate a string
• strerror(3)return string describing error number
• strfmon(3)convert monetary value to a string
• strfromd(3)convert a floating-point value into a string
• strfry(3)randomize a string
• strftime(3)format date and time
• string(3)string operations
• strlen(3)calculate the length of a string
• strncat(3)append non-null bytes from a source array to a string, and null-terminate the result
• strnlen(3)determine the length of a fixed-size string
• strpbrk(3)search a string for any of a set of bytes
• strptime(3)convert a string representation of time to a time tm structure
• strsep(3)extract token from string
• strsignal(3)return string describing signal
• strspn(3)get length of a prefix substring
• strstr(3)locate a substring
• strtod(3)convert ASCII string to floating-point number
• strtoimax(3)convert string to integer
• strtok(3)extract tokens from strings
• strtol(3)convert a string to a long integer
• strtoul(3)convert a string to an unsigned long integer
• strverscmp(3)compare two version strings
• strxfrm(3)string transformation
• swab(3)swap adjacent bytes
• sysconf(3)get configuration information at run time
• sysexits.h(3)exit codes for programs
• syslog(3)send messages to the system logger
• system(3)execute a shell command
• sysv_signal(3)signal handling with System V semantics

T

• tailq(3)implementation of a doubly linked tail queue
• tan(3)tangent function
• tanh(3)hyperbolic tangent function
• tcgetpgrp(3)get and set terminal foreground process group
• tcgetsid(3)get session ID
• telldir(3)return current location in directory stream
• tempnam(3)create a name for a temporary file
• termios(3)get and set terminal attributes, line control, get and set baud rate
• tgamma(3)true gamma function
• time(3)time functions for gawk
• time_t(3)integer time
• timegm(3)inverses of gmtime and localtime
• timer_t(3)timer ID
• timeradd(3)timeval operations
• timespec(3)time in seconds and nanoseconds
• timeval(3)time in seconds and microseconds
• TIMEVAL_TO_TIMESPEC(3)convert between time structures
• tm(3)broken-down time
• tmpfile(3)create a temporary file
• tmpnam(3)create a name for a temporary file
• toascii(3)convert character to ASCII
• toupper(3)convert uppercase or lowercase
• towctrans(3)wide-character transliteration
• towlower(3)convert a wide character to lowercase
• towupper(3)convert a wide character to uppercase
• trunc(3)round to integer, toward zero
• tsearch(3)manage a binary search tree
• ttyname(3)return name of a terminal
• ttyslot(3)find the slot of the current user's terminal in some file
• tzset(3)initialize time conversion information

U

• ualarm(3)schedule signal after given number of microseconds
• ulimit(3)get and set user limits
• undocumented(3)undocumented library functions
• ungetwc(3)push back a wide character onto a FILE stream
• unlocked_stdio(3)nonlocking stdio functions
• unlockpt(3)unlock a pseudoterminal master/slave pair
• updwtmp(3)append an entry to the wtmp file
• uselocale(3)set/get the locale for the calling thread
• usleep(3)suspend execution for microsecond intervals

V

• va_list(3)variable argument list
• void(3)abstract type

W

• wcpcpy(3)copy a wide-character string, returning a pointer to its end
• wcpncpy(3)copy a fixed-size string of wide characters, returning a pointer to its end
• wcrtomb(3)convert a wide character to a multibyte sequence
• wcscasecmp(3)compare two wide-character strings, ignoring case
• wcscat(3)concatenate two wide-character strings
• wcschr(3)search a wide character in a wide-character string
• wcscmp(3)compare two wide-character strings
• wcscpy(3)copy a wide-character string
• wcscspn(3)search a wide-character string for any of a set of wide characters
• wcsdup(3)duplicate a wide-character string
• wcslen(3)determine the length of a wide-character string
• wcsncasecmp(3)compare two fixed-size wide-character strings, ignoring case
• wcsncat(3)concatenate two wide-character strings
• wcsncmp(3)compare two fixed-size wide-character strings
• wcsncpy(3)copy a fixed-size string of wide characters
• wcsnlen(3)determine the length of a fixed-size wide-character string
• wcsnrtombs(3)convert a wide-character string to a multibyte string
• wcspbrk(3)search a wide-character string for any of a set of wide characters
• wcsrchr(3)search a wide character in a wide-character string
• wcsrtombs(3)convert a wide-character string to a multibyte string
• wcsspn(3)get length of a prefix wide-character substring
• wcsstr(3)locate a substring in a wide-character string
• wcstoimax(3)convert wide-character string to integer
• wcstok(3)split wide-character string into tokens
• wcstombs(3)convert a wide-character string to a multibyte string
• wcswidth(3)determine columns needed for a fixed-size wide-character string
• wctob(3)try to represent a wide character as a single byte
• wctomb(3)convert a wide character to a multibyte sequence
• wctrans(3)wide-character translation mapping
• wctype(3)wide-character classification
• wcwidth(3)determine columns needed for a wide character
• wmemchr(3)search a wide character in a wide-character array
• wmemcmp(3)compare two arrays of wide-characters
• wmemcpy(3)copy an array of wide-characters
• wmemmove(3)copy an array of wide-characters
• wmemset(3)fill an array of wide-characters with a constant wide character
• wordexp(3)perform word expansion like a posix-shell
• wprintf(3)formatted wide-character output conversion

X

• xcrypt(3)RFS password encryption
• xdr(3)library routines for external data representation

Y

• y0(3)Bessel functions of the second kind

#

• __ppc_get_timebase(3)get the current value of the Time Base Register on Power architecture and its frequency.
• __ppc_set_ppr_med(3)Set the Program Priority Register
• __ppc_yield(3)Hint the processor to release shared resources
• __setfpucw(3)set FPU control word on i386 architecture (obsolete)
• _Generic(3)type-generic selection