Programming C

The int atoi function (const char * str) in standard C library converts a string pointed to by parameter str to an integer (int type).

The function long int atol (const char * str) in the standard C library converts a string pointed to by parameter str to some long int.

The double strtod function (const char * str, char ** endptr) in Standard C library converts a string pointed to by parameter str to a floating point number (type double).

The function long int strtol (const char * str, char ** endptr, int base) in Standard C library converts part of the original string in str to a value of long int corresponding to

The unsigned function long int strtoul (const char * str, char ** endptr, int base) in Standard C library converts part of the original string in str to a value of long int

The function void * calloc (so-phan-tu, kich-co-phan-tu) allocates the requested memory and returns a pointer to it. The difference between malloc and calloc is: malloc does not

The void free function (void * ptr) frees the previously allocated memory by a call to calloc, malloc, or realloc

The malloc () function allocates the requested memory and returns a pointer to it.

The realloc () function attempts to recover the memory block pointed to by the ptr pointer that was previously allocated with a call to malloc or calloc.

The abort () function stops executing the program abnormally.

Int atexit function (void (* func) (void)) calls function func when the program ends. You can register your end function (func function) wherever you like, but this function will

The void exit (int status) function immediately terminates the calling process. Any file opened by the process is closed and any child process is inherited by the initial process

The int remove (const char * filename) function in Library C standard deletes the filename so it is no longer accessible.

The function int rename (const char * old_filename, const char * new_filename) in Library C standard makes filename referenced, changed from old_filename to new_filename.

The void rewind function (FILE * stream) in Standard C library sets the file location to the beginning of the file in the given stream.

The function void setbuf (FILE * stream, char * buffer) in the standard C Library defines how a Stream is buffered. This function should be called once the file attached to the

The function int setvbuf (FILE * stream, char * buffer, int mode, size_t size) in Standard C Library determines how a Stream should be buffered.

Function FILE * tmpfile (void) in standard C Library Create temporary files in wb + mode. The temporary file created will be automatically deleted when the stream is closed

The function char * tmpnam (char * str) in the C Library standard creates and returns a valid temporary file name (temp file) that did not exist before creation. If str is null,

The int fprintf function (FILE * stream, const char * format, ...) in standard C library sends formatted output to a Stream.