The C++ standard library provides a large number of library functions (under different header files) for performing common tasks.
Search library function
| Title | Description | |
|---|---|---|
| C++ pow() | Computes Power a Number | |
| C++ llrint() | Rounds argument using current rounding mode | |
| C++ remainder() | Returns remainder of x/y | |
| C++ nan() | returns a quiet NaN value | |
| C++ cosh() | Returns Hyperbolic Cosine of an Angle | |
| C++ copysign() | returns num with value of first and sign of second | |
| C++ fma() | Returns Fused Multiply–Accumulate | |
| C++ abs() | returns absolute value of an argument | |
| C++ fabs() | returns absolute value of argument | |
| C++ fdim() | Returns Positive Different Between Arguments | |
| C++ fmin() | returns smallest among two given arguments | |
| C++ fmax() | returns largest among two arguments passed | |
| C++ hypot() | Returns Square Root of sum of square of Arguments | |
| C++ nexttoward() | returns next value after x in direction of y | |
| C++ nextafter() | returns next value after x in direction of y | |
| C++ cbrt() | Computes Cube Root of a Number | |
| C++ sqrt() | Computes Square Root of A Number | |
| C++ remquo() | Computer remainder and stores quotient of x/y | |
| C++ logb() | returns logarithm of |x| | |
| C++ log1p() | returns natural logarithm of x+1. | |
| C++ scalbln() | Scales x by FLT_RADIX to the power n | |
| C++ log2() | returns base2 logarithm of a number | |
| C++ scalbn() | Scales x by FLT_RADIX to the power n | |
| C++ ilogb() | returns integral part of logarithm of |x| | |
| C++ nearbyint() | Rounds argument to using current rounding mode | |
| C++ expm1() | Returns e raised to Power Minus 1 | |
| C++ ldexp() | returns product of x and 2 raised to the power e | |
| C++ frexp() | breaks float to its binary significand | |
| C++ exp2() | Returns 2 raised to a Number | |
| C++ exp() | returns exponential (e) raised to a number | |
| C++ modf() | Breaks Number Into Integral and Fractional Part | |
| C++ log10() | Returns Base 10 Logarithm of a Number | |
| C++ lrint() | Rounds argument using current rounding mode | |
| C++ rint() | Rounds argument using current rounding mode | |
| C++ llround() | Rounds argument to nearest long long int value | |
| C++ lround() | Returns the long int value nearest to the argument | |
| C++ round() | Returns integral value nearest to argument | |
| C++ trunc() | Truncates the demical part of a number | |
| C++ log() | Returns Natural Logarithm of a Number | |
| C++ atanh() | returns arc hyperbolic tangent of a number | |
| C++ asinh() | returns arc hyperbolic sine of a number | |
| C++ acosh() | returns hyperbolic cosine of a number | |
| C++ fmod() | Computes floating point remainder of division | |
| C++ tanh() | returns hyperbolic tangent of an angle | |
| C++ floor() | Returns floor value of decimal number | |
| C++ ceil() | Return ceiling value of number | |
| C++ sinh() | returns hyperbolic sine of an angle | |
| C++ acos() | Returns Inverse cosine a Number | |
| C++ atan2() | Returns Inverse Tangent of a Coordinate | |
| C++ tan() | Returns Tangent of the Argument | |
| C++ atan() | Returns Inverse tangent a Number | |
| C++ asin() | Returns Inverse Sine a Number | |
| C++ sin() | Returns Sine of the Argument | |
| C++ cos() | Returns Cosine of the Argument |
| Title | Description | |
|---|---|---|
| C++ calloc() | allocates block of memory and initializes to zero | |
| C++ wcstombs() | converts wide character string to multibyte seq | |
| C++ mbstowcs() | converts multibyte char string to wide char seq | |
| C++ wctomb() | converts wide character to a multibyte character | |
| C++ mbtowc() | converts multibyte character to a wide character | |
| C++ mblen() | determines size of a multibyte character | |
| C++ lldiv() | computes integral division of two long long int. | |
| C++ llabs() | returns absolute value of a long long int data | |
| C++ ldiv() | computes integral division of long int numbers | |
| C++ labs() | returns absolute value of long or long int number | |
| C++ abs() | returns absolute value of an integer | |
| C++ div() | computes integral quotient and remainder of number | |
| C++ qsort() | sorts array using quick-sort algorithm | |
| C++ bsearch() | performs binary search on sorted array | |
| C++ _Exit() | causes termination without cleanup tasks | |
| C++ quick_exit() | causes termination without cleaning resources | |
| C++ getenv() | returns pointer to environment variable passed | |
| C++ at_quick_exit() | registers function and calls on quick termination | |
| C++ atexit() | registers function to be called on termination | |
| C++ realloc() | reallocates a block of previously allocated memory | |
| C++ malloc() | allocates a block of unitialized memory | |
| C++ free() | deallocates a block of memory | |
| C++ srand() | seeds pseudo random number for rand() | |
| C++ strtoull() | converts string to unsigned long long int | |
| C++ strtoll() | converts string to long long int in C++ | |
| C++ atol() | Converts String to Integer | |
| C++ strtol() | Converts a string to number | |
| C++ atof() | Converts String to Double | |
| C++ strtod() | returns string float to double |
| Title | Description | |
|---|---|---|
| C++ wclog | writes to log stream with wide character | |
| C++ wcerr | prints to error stream as wide character type | |
| C++ wcout | displays wide characters (Unicode) to screen | |
| C++ wcin | accepts input in wide character type | |
| C++ clog | used for streaming logs | |
| C++ cerr | writes to error stream | |
| C++ cout | displays output to output device i.e monitor | |
| C++ cin | accepts input from user |
| Title | Description | |
|---|---|---|
| C++ strxfrm() | transform byte string into implementation def form | |
| C++ strcoll() | compares two null terminated string | |
| C++ strlen() | returns length of given string | |
| C++ strerror() | gives description of system error code | |
| C++ memset() | copies character to beginning of string n times | |
| C++ strtok() | split string based on delimiter | |
| C++ strstr() | finds first occurrence of a substring in string | |
| C++ strspn() | gives length of maximum initial segment | |
| C++ strrchr() | searches last occurence of a character in string | |
| C++ strpbrk() | search characters in one string in another string | |
| C++ strcspn() | searches a string for characters in another string | |
| C++ strchr() | searches for character in string | |
| C++ memchr() | searches for character in string | |
| C++ strncmp() | compares two strings lexographically | |
| C++ strcmp() | compare two strings | |
| C++ memcmp() | compares two pointer objects | |
| C++ strncat() | appends string to end of another string | |
| C++ strcat() | appends copy of string to end of another string | |
| C++ strncpy() | copies character string from source to destination | |
| C++ strcpy() | copies character string from source to destination | |
| C++ memmove() | copies memory even if there is overlapping blocks | |
| C++ memcpy() | copies block of memory from source to destination |
| Title | Description | |
|---|---|---|
| C++ toupper() | converts a given character to uppercase | |
| C++ tolower() | converts a given character to lowercase | |
| C++ isxdigit() | checks if given character is hexadecimal character | |
| C++ isupper() | check if given character is uppercase or not | |
| C++ isspace() | check if given character is whitespace character | |
| C++ ispunct() | check if given character is punctuation character | |
| C++ isprint() | check if given character is printable or not | |
| C++ islower() | checks if given character is lowercase | |
| C++ isgraph() | checks if given character is graphic or not | |
| C++ isdigit() | checks if given character is a digit or not | |
| C++ iscntrl() | checks if given character is control character | |
| C++ isblank() | checks if given character is a blank character | |
| C++ isalpha() | checks if given character is alphabet or not |
| Title | Description | |
|---|---|---|
| C++ raise() | sends signal to the program | |
| C++ signal() | sets error handler for specifiied signal |
| Title | Description | |
|---|---|---|
| C++ localeconv() | returns current locale formatting rules | |
| C++ setlocale() | sets locale information for the current program |
| Title | Description | |
|---|---|---|
| C++ iswdigit() | checks if given wide character is digit or not | |
| C++ wctype() | returns wide character classification | |
| C++ wctrans() | returns current transformation for wide character | |
| C++ towctrans() | transforms a given wide character | |
| C++ iswctype() | checks if given wide char has certain property | |
| C++ towupper() | converts given wide character to uppercase | |
| C++ towlower() | converts given wide character to lowercase | |
| C++ iswxdigit() | checks if given wide character is hexadecimal num | |
| C++ iswupper() | checks if given wide character is uppercase | |
| C++ iswspace() | checks if given wide character is wide whitespace | |
| C++ iswpunct() | checks if given wide character is punctuation | |
| C++ iswprint() | checks if given wide character can be printed | |
| C++ iswlower() | checks if given wide character is lowercase | |
| C++ iswgraph() | checks if wide char has graphical representation | |
| C++ iswcntrl() | checks if given wide char is control character | |
| C++ iswblank() | checks if given wide character is blank character | |
| C++ iswalpha() | checks if given wide character is an alphabet | |
| C++ iswalnum() | checks if given wide character is alphanumeric |
| Title | Description | |
|---|---|---|
| C++ getc() | reads next character from input stream | |
| C++ fseek() | sets file position indicator for given file stream | |
| C++ ungetc() | push previously read character back to the stream | |
| C++ vsscanf() | read data from a string buffer | |
| C++ vscanf() | read data from stdin | |
| C++ vfscanf() | read data from a file stream | |
| C++ freopen() | opens a new file with stream associated to another | |
| C++ fflush() | flushes any buffered data to the respective device | |
| C++ setvbuf() | change or specify buffering mode and buffer size | |
| C++ perror() | prints error to stderr | |
| C++ ferror() | checks for errors in given stream | |
| C++ feof() function | checks if file stream EOF has been reached or not | |
| C++ clearerr() | resets error flags and EOF indicator for stream | |
| C++ rewind() | sets file position to beginning of stream | |
| C++ ftell() | returns current position of file pointer | |
| C++ fsetpos() | sets stream file pointer to given position | |
| C++ fgetpos() | gets current file position | |
| C++ fwrite() | writes specified number of characters to stream | |
| C++ fread() | reads specified no. of characters from stream | |
| C++ puts() | writes string to stdout | |
| C++ putchar() | writes a character to stdout | |
| C++ putc() | writes character to given output stream | |
| C++ gets() | reads line from stdin | |
| C++ getchar() | reads next character from stdin | |
| C++ fputs() | writes string to file stream | |
| C++ fputc() | writes character to given output stream | |
| C++ fgets() | reads n number of characters from file stream | |
| C++ fgetc() | reads the next character from given input stream | |
| C++ vsprintf() | write formatted string to a string buffer | |
| C++ vsnprintf() | write formatted string to string buffer | |
| C++ vprintf() | printf but takes args from vlist instead | |
| C++ vfprintf() | write formatted string to file stream | |
| C++ sscanf() | read data from string buffer | |
| C++ sprintf() | write a formatted string to buffer | |
| C++ snprintf() | write formatted string to character string buffer | |
| C++ scanf | read data form stdin | |
| C++ printf() | write formatted string to stdout | |
| C++ fscanf() | read data from file stream | |
| C++ fprintf() | write a formatted string to file stream | |
| C++ setbuf() | sets the internal buffer to be used for I/O | |
| C++ fopen() | opens specified file | |
| C++ fclose() | closes given file stream | |
| C++ tmpnam() | generates unique filename | |
| C++ tmpfile() | creates temporary file with auto-generated name | |
| C++ rename() | renames or moves specified file | |
| C++ remove() | deletes the specified file |
| Title | Description | |
|---|---|---|
| C++ wcscoll() | compares two null terminated wide string | |
| C++ wcstoull() | converts wide string num to unsigned long long | |
| C++ wcstoul() | converts wide str of given base to unsigned long | |
| C++ wcstoll() | converts wide string of specified base to int | |
| C++ wcsftime() | converts given date and time to wide character str | |
| C++ wmemset() | copies single wide char for a certain num of time | |
| C++ wmemmove() | moves wide chars from src to dest | |
| C++ wmemcpy() | copies specified num of wide char from src to dest | |
| C++ wmemcmp() | compares wide chars of two wide strings | |
| C++ wmemchr() | searches for first occurrence of wide char | |
| C++ wcsxfrm() | transforms wide string to implementation defined | |
| C++ wcsstr() | finds first occurrence of wide substring in a str | |
| C++ wcsspn() | returns length of maximum initial segment | |
| C++ wcsrchr() | searches last occurrence of wide char in string | |
| C++ wcspbrk() | searches for set of wide char in given wide string | |
| C++ wcsncpy() | copies specified number of wide characters | |
| C++ wcsncmp() | compares specified number of wide char of strings | |
| C++ wcsncat() | appends specified num of wide char to another str | |
| C++ wcslen() | returns length of the given wide string | |
| C++ wcscspn() | returns number of wide char before first occurence | |
| C++ wcscpy() | copies wide character string from source to dest | |
| C++ wcscmp() | lexicographically compares two wide string | |
| C++ wcschr() | searches for a wide character in a wide string | |
| C++ wcscat() | appends copy of wide string to the end of another | |
| C++ wcsrtombs() | convert wide char seq to narrow multibyte char seq | |
| C++ wctob() | converts wide character to single byte character | |
| C++ wcrtomb() | convert wide character to its narrow multibyte rep | |
| C++ mbsrtowcs() | convert narrow multibyte char seq to wide char seq | |
| C++ mbsinit() | describe initial conversion state of mbstate_t obj | |
| C++ mbrtowc() | converts narrow multibyte char to wide char | |
| C++ mbrlen() | determines size in bytes of a multibyte character | |
| C++ btowc() | converts character to its wide character | |
| C++ wcstok() | returns next token in null terminated wide string | |
| C++ wcstold() | converts wide string float number to long double | |
| C++ wcstol() | converts wide string float number to long int | |
| C++ wcstof() | converts wide string float number to float | |
| C++ wcstod() | converts wide string float number to double | |
| C++ wscanf() | reads wide character from stdin | |
| C++ wprintf() | write formatted wide string to stdout | |
| C++ vwscanf() | read wide character from stdin | |
| C++ vwprintf() | write formatted wide string to stdout | |
| C++ vswscanf() | read wide character string from wide string buffer | |
| C++ vswprintf() | write formatted wide string to wide string buffer | |
| C++ vfwscanf() | read wide character string from a file stream | |
| C++ vfwprintf() | write formatted wide string to a file stream | |
| C++ ungetwc() | push previously read wide character back to stream | |
| C++ swscanf() | reads wide character from wide string buffer | |
| C++ swprintf() | write formatted wide string to wide string buffer | |
| C++ putwchar() | writes wide character to stdout | |
| C++ putwc() | writes wide character to the given output stream | |
| C++ getwchar() | reads next wide character from stdin | |
| C++ getwc() | reads next wide character from input stream | |
| C++ fwscanf() | reads wide character from file stream | |
| C++ fwprintf() | write formatted wide string to a file stream | |
| C++ fwide() | set or query orientation of given file stream | |
| C++ fputws() | writes wide string except null wide char to output | |
| C++ fputwc() | writes wide character to the given output stream | |
| C++ fgetws() | reads specified num of wide characters from stream | |
| C++ fgetwc() | reads next wide character from given input stream |
| Title | Description | |
|---|---|---|
| C++ mbrtoc32() | converts narrow multibyte char to 32 bit char | |
| C++ mbrtoc16() | converts narrow multibyte char to 16 bit char | |
| C++ c32rtomb() | converts 32 bit char to narrow multibyte char | |
| C++ c16rtomb() | converts 16 bit char to narrow multibyte char |
| Title | Description | |
|---|---|---|
| C++ longjmp() and setjmp() | restores previously saved environment |
| Title | Description | |
|---|---|---|
| C++ fetestexcept() | tests floating point exception | |
| C++ feupdateenv() | updates floating point environment | |
| C++ feholdexcept() | saves and clear floating point status flags | |
| C++ fesetenv() | set floating point environment | |
| C++ fesetround() | set rounding direction | |
| C++ fegetenv() | store status of floating point env in an object | |
| C++ fegetround() | gets round direction mode | |
| C++ fesetexceptflag() | sets given floating point exceptions to the env | |
| C++ fegetexceptflag() | gets floating point exception flags | |
| C++ feraiseexcept() | raises floating point exceptions specified | |
| C++ feclearexcept() | attempts to clear floating point exception flags |
| Title | Description | |
|---|---|---|
| C++ strftime() | converts calendar time to multibyte character str | |
| C++ mktime() | converts local calendar time to time since epoch | |
| C++ localtime() | converts given time since epoch to local time | |
| C++ gmtime() | converts given time since epoch to UTC time | |
| C++ ctime() | converts time since epoch to char representation | |
| C++ asctime() | converts calendar time to character representation | |
| C++ time() | returns current calendar time | |
| C++ difftime() | computes difference between two times in seconds | |
| C++ clock() | returns processor time consumed by program |