问题
I installed NetBeans for C successfully, but I don't know what is wrong because whenever I write any code it says "build successful" but it does not execute. Nothing happens when I hit the run button, Netbeans just compiles the code but nothing is displayed on screen.
The Following is the simple code:
int main(void) {
int a=0;
printf("input any number");
scanf("%d",&a);
return (EXIT_SUCCESS);
}
And here is its compilation:
""/C/MinGW/msys/1.0/bin/make.exe" -f nbproject/Makefile-Debug.mk QMAKE= SUBPROJECTS= .build-conf
make.exe[1]: Entering directory `/c/Users/timekeeper/Documents/NetBeansProjects/ft'
"/C/MinGW/msys/1.0/bin/make.exe" -f nbproject/Makefile-Debug.mk dist/Debug/MinGW-Windows/ft.exe
make.exe[2]: Entering directory `/c/Users/timekeeper/Documents/NetBeansProjects/ft'
mkdir -p build/Debug/MinGW-Windows
rm -f "build/Debug/MinGW-Windows/main.o.d"
gcc -std=c99 -c -g -MMD -MP -MF "build/Debug/MinGW-Windows/main.o.d" -o build/Debug/MinGW-Windows/main.o main.c
mkdir -p dist/Debug/MinGW-Windows
gcc -std=c99 -o dist/Debug/MinGW-Windows/ft build/Debug/MinGW-Windows/main.o
make.exe[2]: Leaving directory `/c/Users/timekeeper/Documents/NetBeansProjects/ft'
make.exe[1]: Leaving directory `/c/Users/timekeeper/Documents/NetBeansProjects/ft'
BUILD SUCCESSFUL (total time: 34s)
""
What should i do? Thanks in advance
回答1:
The stdout
stream is line-buffered. That means whatever you fwrite
or printf
, etc. to stdout
will not actually be written to your terminal until a newline character (\n
) is encountered.
So your program has your string buffered, and is blocked on the scanf
, waiting for your input from stdin
. As soon as this happens, your console window is closing, and you never see the print.
To remedy this, either add a newline character at the end of your string:
printf("input any number:\n"); // Newline at end of string
or manually cause stdout
to be flushed:
printf("input any number: ");
fflush(stdout); // Force stdout to be flushed to the console
Furthermore, I'm assuming that the (total time: 34s)
figure includes the time the program was waiting for you to type something. You were incredibly patient, and after ~34 seconds, finally mashed something on the keyboard, after which the program ended and the console window closed.
Or, if Netbeans isn't opening a separate console window, this is all happening in one of those MDI panes of the Netbeans IDE.
来源:https://stackoverflow.com/questions/26900167/c-program-compiles-but-does-not-execute