Input and Output Functions
==========================

   Functions that perform input from a stdio stream, and functions that
output to a stdio stream.  Passing a NULL pointer for a STREAM argument
to any of these functions will make them read from `stdin' and write to
`stdout', respectively.

   When using any of these functions, it is a good idea to include
`stdio.h' before `gmp.h', since that will allow `gmp.h' to define
prototypes for these functions.

 - Function: size_t mpf_out_str (FILE *STREAM, int BASE, size_t
          N_DIGITS, mpf_t OP)
     Output OP on stdio stream STREAM, as a string of digits in base
     BASE.  The base may vary from 2 to 36.  Print at most N_DIGITS
     significant digits, or if N_DIGITS is 0, the maximum number of
     digits accurately representable by OP.

     In addition to the significant digits, a leading `0.' and a
     trailing exponent, in the form `eNNN', are printed.  If BASE is
     greater than 10, `@' will be used instead of `e' as exponent
     delimiter.

     Return the number of bytes written, or if an error occurred,
     return 0.

 - Function: size_t mpf_inp_str (mpf_t ROP, FILE *STREAM, int BASE)
     Input a string in base BASE from stdio stream STREAM, and put the
     read float in ROP.  The string is of the form `M@N' or, if the
     base is 10 or less, alternatively `MeN'.  `M' is the mantissa and
     `N' is the exponent.  The mantissa is always in the specified
     base.  The exponent is either in the specified base or, if BASE is
     negative, in decimal.

     The argument BASE may be in the ranges 2 to 36, or -36 to -2.
     Negative values are used to specify that the exponent is in
     decimal.

     Unlike the corresponding `mpz' function, the base will not be
     determined from the leading characters of the string if BASE is 0.
     This is so that numbers like `0.23' are not interpreted as octal.

     Return the number of bytes read, or if an error occurred, return 0.