section 3posix · Library functions 📚

#

• _Exit(3posix)terminate a process✨
• _longjmp(3posix)non-local goto✨
• _tolower(3posix)transliterate uppercase characters to lowercase✨
• _toupper(3posix)transliterate lowercase characters to uppercase✨

A

• a64l(3posix)convert between a 32-bit integer and a radix-64 ASCII string✨
• abort(3posix)generate an abnormal process abort✨
• abs(3posix)return an integer absolute value✨
• accept(3posix)accept a new connection on a socket✨
• access(3posix)determine accessibility of a file descriptor✨
• acos(3posix)arc cosine functions✨
• acosh(3posix)inverse hyperbolic cosine functions✨
• acosl(3posix)arc cosine functions✨
• aio_cancel(3posix)cancel an asynchronous I/O request✨
• aio_error(3posix)retrieve errors status for an asynchronous I/O operation✨
• aio_fsync(3posix)asynchronous file synchronization✨
• aio_read(3posix)asynchronous read from a file✨
• aio_return(3posix)retrieve return status of an asynchronous I/O operation✨
• aio_suspend(3posix)wait for an asynchronous I/O request✨
• aio_write(3posix)asynchronous write to a file✨
• alarm(3posix)schedule an alarm signal✨
• alphasort(3posix)scan a directory✨
• asctime(3posix)convert date and time to a string✨
• asin(3posix)arc sine function✨
• asinh(3posix)inverse hyperbolic sine functions✨
• asinl(3posix)arc sine function✨
• assert(3posix)insert program diagnostics✨
• atan(3posix)arc tangent function✨
• atan2(3posix)arc tangent functions✨
• atanf(3posix)arc tangent function✨
• atanh(3posix)inverse hyperbolic tangent functions✨
• atanl(3posix)arc tangent function✨
• atexit(3posix)register a function to run at process termination✨
• atof(3posix)convert a string to a double-precision number✨
• atoi(3posix)convert a string to an integer✨
• atol(3posix)convert a string to a long integer✨

B

• basename(3posix)return the last component of a pathname✨
• bind(3posix)bind a name to a socket✨
• bsearch(3posix)binary search a sorted table✨
• btowc(3posix)single byte to wide character conversion✨

C

• cabs(3posix)return a complex absolute value✨
• cacos(3posix)complex arc cosine functions✨
• cacosh(3posix)complex arc hyperbolic cosine functions✨
• cacosl(3posix)complex arc cosine functions✨
• calloc(3posix)a memory allocator✨
• carg(3posix)complex argument functions✨
• casin(3posix)complex arc sine functions✨
• casinh(3posix)complex arc hyperbolic sine functions✨
• casinl(3posix)complex arc sine functions✨
• catan(3posix)complex arc tangent functions✨
• catanh(3posix)complex arc hyperbolic tangent functions✨
• catanl(3posix)complex arc tangent functions✨
• catclose(3posix)close a message catalog descriptor✨
• catgets(3posix)read a program message✨
• catopen(3posix)open a message catalog✨
• cbrt(3posix)cube root functions✨
• ccos(3posix)complex cosine functions✨
• ccosh(3posix)complex hyperbolic cosine functions✨
• ccosl(3posix)complex cosine functions✨
• ceil(3posix)ceiling value function✨
• cexp(3posix)complex exponential functions✨
• cfgetispeed(3posix)get input baud rate✨
• cfgetospeed(3posix)get output baud rate✨
• cfsetispeed(3posix)set input baud rate✨
• cfsetospeed(3posix)set output baud rate✨
• chdir(3posix)change working directory✨
• chmod(3posix)change mode of a file✨
• chown(3posix)change owner and group of a file✨
• cimag(3posix)complex imaginary functions✨
• clearerr(3posix)clear indicators on a stream✨
• clock(3posix)report CPU time used✨
• clock_getcpuclockid(3posix)access a process CPU-time clock (ADVANCED REALTIME)✨
• clock_getres(3posix)clock and timer functions✨
• clock_nanosleep(3posix)high resolution sleep with specifiable clock✨
• clock_settime(3posix)clock and timer functions✨
• clog(3posix)complex natural logarithm functions✨
• close(3posix)close a file descriptor✨
• closedir(3posix)close a directory stream✨
• closelog(3posix)control system log✨
• confstr(3posix)get configurable variables✨
• conj(3posix)complex conjugate functions✨
• connect(3posix)connect a socket✨
• copysign(3posix)number manipulation function✨
• cos(3posix)cosine function✨
• cosh(3posix)hyperbolic cosine functions✨
• cosl(3posix)cosine function✨
• cpow(3posix)complex power functions✨
• cproj(3posix)complex projection functions✨
• creal(3posix)complex real functions✨
• creat(3posix)create a new file or rewrite an existing one✨
• crypt(3posix)string encoding function (CRYPT)✨
• csin(3posix)complex sine functions✨
• csinh(3posix)complex hyperbolic sine functions✨
• csinl(3posix)complex sine functions✨
• csqrt(3posix)complex square root functions✨
• ctan(3posix)complex tangent functions✨
• ctanh(3posix)complex hyperbolic tangent functions✨
• ctanl(3posix)complex tangent functions✨
• ctermid(3posix)generate a pathname for the controlling terminal✨
• ctime(3posix)convert a time value to a date and time string✨

D

• daylight(3posix)daylight savings time flag✨
• dbm_clearerr(3posix)database functions✨
• difftime(3posix)compute the difference between two calendar time values✨
• dirfd(3posix)extract the file descriptor used by a DIR stream✨
• dirname(3posix)report the parent directory name of a file pathname✨
• div(3posix)compute the quotient and remainder of an integer division✨
• dlclose(3posix)close a symbol table handle✨
• dlerror(3posix)get diagnostic information✨
• dlopen(3posix)open a symbol table handle✨
• dlsym(3posix)get the address of a symbol from a symbol table handle✨
• dprintf(3posix)print formatted output✨
• drand48(3posix)generate uniformly distributed pseudo-random numbers✨
• dup(3posix)duplicate an open file descriptor✨
• duplocale(3posix)duplicate a locale object✨

E

• encrypt(3posix)encoding function (CRYPT)✨
• endgrent(3posix)group database entry functions✨
• endhostent(3posix)network host database functions✨
• endnetent(3posix)network database functions✨
• endprotoent(3posix)network protocol database functions✨
• endpwent(3posix)user database functions✨
• endservent(3posix)network services database functions✨
• endutxent(3posix)user accounting database functions✨
• environ(3posix)array of character pointers to the environment strings✨
• erand48(3posix)generate uniformly distributed pseudo-random numbers✨
• erf(3posix)error functions✨
• erfc(3posix)complementary error functions✨
• erff(3posix)error functions✨
• errno(3posix)error return value✨
• exec(3posix)execute a file✨
• exit(3posix)terminate a process✨
• exp(3posix)exponential function✨
• exp2(3posix)exponential base 2 functions✨
• expm1(3posix)compute exponential functions✨

F

• fabs(3posix)absolute value function✨
• faccessat(3posix)determine accessibility of a file relative to directory file descriptor✨
• fattach(3posix)attach a STREAMS-based file descriptor to a file in the file system name space (STREAMS)✨
• fchdir(3posix)change working directory✨
• fchmod(3posix)change mode of a file✨
• fchmodat(3posix)change mode of a file relative to directory file descriptor✨
• fchown(3posix)change owner and group of a file✨
• fchownat(3posix)change owner and group of a file relative to directory file descriptor✨
• fclose(3posix)close a stream✨
• fcntl(3posix)file control✨
• FD_CLR(3posix)macros for synchronous I/O multiplexing✨
• fdatasync(3posix)synchronize the data of a file (REALTIME)✨
• fdetach(3posix)detach a name from a STREAMS-based file descriptor (STREAMS)✨
• fdim(3posix)compute positive difference between two floating- point numbers✨
• fdopen(3posix)associate a stream with a file descriptor✨
• fdopendir(3posix)open directory associated with file descriptor✨
• feclearexcept(3posix)clear floating-point exception✨
• fegetenv(3posix)get and set current floating-point environment✨
• fegetexceptflag(3posix)get and set floating-point status flags✨
• fegetround(3posix)get and set current rounding direction✨
• feholdexcept(3posix)save current floating-point environment✨
• feof(3posix)test end-of-file indicator on a stream✨
• feraiseexcept(3posix)raise floating-point exception✨
• ferror(3posix)test error indicator on a stream✨
• fesetenv(3posix)set current floating-point environment✨
• fesetexceptflag(3posix)set floating-point status flags✨
• fesetround(3posix)set current rounding direction✨
• fetestexcept(3posix)test floating-point exception flags✨
• feupdateenv(3posix)update floating-point environment✨
• fexecve(3posix)execute a file✨
• fflush(3posix)flush a stream✨
• ffs(3posix)find first set bit✨
• fgetc(3posix)get a byte from a stream✨
• fgetpos(3posix)get current file position information✨
• fgets(3posix)get a string from a stream✨
• fgetwc(3posix)get a wide-character code from a stream✨
• fgetws(3posix)get a wide-character string from a stream✨
• fileno(3posix)map a stream pointer to a file descriptor✨
• flockfile(3posix)stdio locking functions✨
• floor(3posix)floor function✨
• fma(3posix)floating-point multiply-add✨
• fmax(3posix)determine maximum numeric value of two floating- point numbers✨
• fmemopen(3posix)open a memory buffer stream✨
• fmin(3posix)determine minimum numeric value of two floating- point numbers✨
• fmod(3posix)floating-point remainder value function✨
• fmtmsg(3posix)display a message in the specified format on standard error and/or a system console✨
• fnmatch(3posix)match a filename string or a pathname✨
• fopen(3posix)open a stream✨
• fork(3posix)create a new process✨
• fpathconf(3posix)get configurable pathname variables✨
• fpclassify(3posix)classify real floating type✨
• fprintf(3posix)print formatted output✨
• fputc(3posix)put a byte on a stream✨
• fputs(3posix)put a string on a stream✨
• fputwc(3posix)put a wide-character code on a stream✨
• fputws(3posix)put a wide-character string on a stream✨
• fread(3posix)binary input✨
• free(3posix)free allocated memory✨
• freeaddrinfo(3posix)get address information✨
• freelocale(3posix)free resources allocated for a locale object✨
• freopen(3posix)open a stream✨
• frexp(3posix)extract mantissa and exponent from a double precision number✨
• fscanf(3posix)convert formatted input✨
• fseek(3posix)reposition a file-position indicator in a stream✨
• fsetpos(3posix)set current file position✨
• fstat(3posix)get file status✨
• fstatat(3posix)get file status✨
• fstatvfs(3posix)get file system information✨