问题
I'm using mingw with msys and mintty on windows. I have a problem that msys and mintty are somehow not flushing output until a command is finished. This means I can't really run any interactive programs.
For example, if I have in C:
printf("Test\n");
the output won't appear until the program has terminated. However, if I have:
printf("Test\n"); fflush(stdout);
then the output appears immediately. If I use msys without mintty or the windows console, then everything works normally.
So my question, what's going on with msys and mintty?
回答1:
This can be an issue when msys uses the rxvt shell under a number of scenarios. In cases where I see this problem, I ask msys to use the native Windows shell for its console. For example:
C:\MinGW\msys\1.0\msys.bat --no-rxvt
I thought that modern MSYS installations default to using the native shell as MSYS developers seem to prefer it. I have other issues with the native shell that drive me to use the rxvt shell, so I do infrequently run into this issue.
C:\MinGW\msys\1.0\msys.bat --rxvt
I find that the rxvt shell usually works fine except for certain applications that are built as "console" utilities meant to run from a command-line.
回答2:
The only thing that worked for me was to precede the command with winpty ...
$ winpty java ClassName
It causes unbuffered output to be 3x slower and buffered output to be 5x slower (in my case, with Java).
To always have a command invisibly invoked by winpty ...
$ cd ~
$ pwd -W
... add the following line to .bashrc ...
alias java="winpty java"
... then restart terminal and ignore the (one-time) warning message.
来源：https://stackoverflow.com/questions/35109086/msys-not-flushing-output