(ANSI) C Language Functions Reference
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C Language Reference Tables
C Library Functions
- abort() - Abort the current process
- abs() - Absolute value
- acos() - the arc cosine of x in radians
- asctime() - Convert tm structure to string
- asin() - the arc sine of x in radians
- atan() - the arc tangent of x in radians
- atan2() - the arc tangent in radians of y/x
- atexit() - Set function that must be executed on exit
- atof() - Convert a string to a double
- atoi() - Convert a string to an integer
- atol() - Convert a string to a long integer
- bsearch() - Binary search in array
- calloc() - Allocate space for an array in memory
- ceil() - the smallest integer value greater than or equal to x
- clock() - Clock ticks elapsed since the start of the program
- cos() - the cosine of a radian angle
- cosh() - the hyperbolic cosine
- ctime() - Convert time_t value to string
- difftime() - Difference between two times
- div() - Integral division
- exit() - Terminate calling process
- exp() - exponential value
- fabs() - the absolute value of x
- floor() - the largest integer value less than or equal to x
- fmod() - the remainder of x divided by y
- free() - De-allocate space in memory
- frexp() - significand and exponent
- getenv() - Get the environment string
- gmtime() - Convert calendar time to UTC
- isalnum() - Alphanumeric test
- isalpha() - Alphabetic test
- iscntrl() - Control character test
- isdigit() - Decimal digit test
- isgraph() - Printing character test (Space is not included)
- islower() - Lower case letter test
- isprint() - Printing character test (Space included)
- ispunct() - Printing character (except space,digit,letter)
- isspace() - Space, tab, vtab, formfeed, newline, cr test
- isupper() - Upper case letter test
- isxdigit() - Hexidecimal digit test
- labs() - Absolute value
- ldexp() - return x multiplied by 2 raised to the power of exponent
- ldiv() - Integral division
- localtime() - Convert calendar time to local time
- log() - the natural logarithm (base-e logarithm)
- log10() - the common logarithm (base-10 logarithm)
- malloc() - Allocate a memory block
- mblen() - Get length of a multi-byte character
- mbtowc() - Convert a multi-byte character to wide character
- memchr() - Pointer to the first occurence c in the first n bytes of a memory area
- memcmp() - Compare n characters of target with source
- memcpy() - Copy n characters from source to target
- memmove() - Copy n characters from source to target (even with overlap)
- memset() - Copies x into a buffer y and does this n times.
- mktime() - Convert the tm structure to time_t
- modf() - break into fractional and integral
- pow() - x raised to the power of y
- qsort() - Sort elements of array
- rand() - Generate random number
- realloc() - Reallocate a memory block
- sin() - the sine of a radian angle
- sinh() - the hyperbolic sine
- sqrt() - the square root
- srand() - Initialize random number generator
- strcat() - Concatenates one string onto the end of another string
- strchr() - Pointer to first occurrence of x in a string
- strcmp() - Compares two strings
- strcpy() - Copy of a string
- strftime() - Format date and time
- strlen() - Length of a string
- strncat() - Concatenates up to n characters
- strncmp() - Compares up to n characters
- strncpy() - Copy of a string up to n characters
- strrchr() - Pointer to last occurrence of x in a string
- strstr() - Pointer to first occurrence of x in a string
- strtod() - Convert a string to a double
- strtol() - Convert a string to a long integer
- strtoul() - Convert a string to an unsigned long integer
- system() - Execute system commands
- tan() - the tangent of a radian angle
- tanh() - the hyperbolic tangent
- time() - Current calendar time
- tolower() - Convert to lower case
- toupper() - Convert to upper case