fputc, fputs, putc, putchar, puts - output of characters and strings
c, FILE *stream);
int fputs(const char *s, FILE *stream);
int putc(int c, FILE *stream);
int putchar(int c);
int puts(const char *s);
fputc() writes the character c, cast to an
unsigned char, to stream.
fputs() writes the string s to stream,
without its trailing '0'.
putc() is equivalent to fputc() except that it
may be implemented as a macro which evaluates stream
more than once.
putchar(c); is equivalent to
puts() writes the string s and a trailing
newline to stdout.
Calls to the functions described here can be mixed with each
other and with calls to other output functions from the
stdio library for the same output
fputc(), putc() and putchar() return
the character written as an unsigned char cast to an
int or EOF on error.
puts() and fputs() return a non - negative
number on success, or EOF on error.
ANSI - C, POSIX.1
It is not advisable to mix calls to output functions from
the stdio library with low - level calls to
write() for the file descriptor associated with the
same output stream; the results will be undefined and very
probably not what you want.
write(2), fopen(3), fwrite(3),
scanf(3), gets(3), fseek(3),