Converting double to char* in C++ with high performance

Question

My application needs to convert double values to char* to write to a pipe that accepts only characters. The usual ways of doing this are using the sprintf() functio

Answer 1

Are you in control of both ends of the pipe? Are you just trying to tunnel doubles through or do you need a valid text representation of the double?

If you are just tunneling and the pipe is 8 bit clean then use one of the answers above.

If you need a string use one of the other answers above.

If your problem is that the pipe is only 7 bits wide, then convert to radix 64 on write and back again on read.