GETS(3) Linux Programmer's Manual GETS(3)
fgetc, fgets, getc, getchar, gets, ungetc - input of characters and strings
int fgetc(FILE *stream);
char *fgets(char *s, int size, FILE *stream);
int getc(FILE *stream);
char *gets(char *s);
int ungetc(int c, FILE *stream);
fgetc() reads the next character from stream and returns it as an unsigned char cast to an int, or EOF on end of file or error.
getc() is equivalent to fgetc() except that it may be implemented as a macro which evaluates stream more than once.
getchar() is equivalent to getc(stdin).
gets() reads a line from stdin into the buffer pointed to by s until either a terminating newline or EOF, which it replaces with '