在Qt控制台应用程序中读取和写入QProcess
注意：这似乎是一个具体的问题，但希望它可以编辑为所有相关
我需要与QProcess对象进行交互。
问题：
在调用QProcess:write(input)之后，我没有从QProcess获得任何输出QProcess:write(input)
更多信息：
阅读文档页面让我在下面创建一个示例：
我有一个请求用户输入的脚本，最后根据用户输入显示和适当的消息。
测试：
将“日志”功能添加到我的脚本进行测试后，会发生以下情况：
qDebug() << p->readAll() ） QProcess输入（由脚本'日志输出'确认） 在此之后，没有收到任何输出。 以下两条调试语句都会触发（即每个都等待30秒）
if (!p->waitForReadyRead()) {
qDebug() << "waitForReadyRead() [false] : CODE: " << QVariant(p->error()).toString() << " | ERROR STRING: " << p->errorString();
}
if (!p->waitForFinished()) {
qDebug() << "waitForFinished() [false] : CODE: " << QVariant(p->error()).toString() << " | ERROR STRING: " << p->errorString();
}
其次是：
QString s = QString(p->readAll() + p->readAllStandardOutput());
其中s是一个空字符串。
问题是s应包含“成功”或“失败”
调用代码：
QString cmd = QString("sh -c "/path/to/bashscript.sh"");
QString input = QString("Name");
QString result = runCommand(cmd, input)
流程代码：
//takes 2 parameters,
// cmd which is the code to be executed by the shell
// input which acts as the user input
QString runCommand(QString cmd, QString input){
QProcess *p = new QProcess(new QObject());
p->setProcessChannelMode(QProcess::MergedChannels); //no actual reason to do this
p->start(cmd);
if (p->waitForStarted()) {
if (!p->waitForReadyRead()) {
qDebug() << "waitForReadyRead() [false] : CODE: " << QVariant(p->error()).toString() << " | ERROR STRING: " << p->errorString();
}
if (!p->waitForFinished()) {
//reads current stdout, this will show the input request from the bash script
//e.g. please enter your name:
qDebug() << p->readAll();
//here I write the input (the name) to the process, which is received by the script
p->write(ps.toLatin1());
//the script should then display a message i.e. ("success" o "failed")
if (!p->waitForReadyRead()) {
qDebug() << "waitForReadyRead() [false] : CODE: " << QVariant(p->error()).toString() << " | ERROR STRING: " << p->errorString();
}
if (!p->waitForFinished()) {
qDebug() << "waitForFinished() [false] : CODE: " << QVariant(p->error()).toString() << " | ERROR STRING: " << p->errorString();
}
}
QString s = QString(p->readAll() + p->readAllStandardOutput());
return s;
}
else{
qDebug() << "waitForStarted() [false] : CODE: " << QVariant(p->error()).toString() << " | ERROR STRING: " << p->errorString();
}
p->waitForFinished();
p->kill();
return QString();
}
script.sh （ -rwxrwxr-x ）
#!/bin/bash
#returns
# "success" on non empty $n value
# "failed: on empty $n value
#
echo "enter your name:"
read n
if [[ ! -z $n ]];
then
echo "success"
exit 0;
else
echo "failed"
exit 1;
fi
UPDATE
@KevinKrammer我修改了运行命令，就像你说的，同样使用QStringList和args。
仍然没有得到输出，事实上waitForReadyRead()和waitForFinished()立即returns false 。
呼叫：
QString r = runCommand(QString("text"));
流程代码：
QString runCommand(QString input){
QProcess *p = new QProcess(new QObject());
p->setProcessChannelMode(QProcess::MergedChannels);
//script is the same script refered to earlier, and the `cd /home/dev` IS required
p->start("sh", QStringList() << "-c" << "cd /home/dev" << "./script");
;
if (p->waitForStarted()) {
if (!p->waitForReadyRead(5000)) {
qDebug() << "waitForReadyRead() [false] : CODE: " << QVariant(p->error()).toString() << " | ERROR STRING: " << p->errorString();
}
qDebug() << p->readAll();
p->write(input.toLatin1());
if(!p->waitForFinished(5000)){
qDebug() << "waitForFinished() [false] : CODE: " << QVariant(p->error()).toString() << " | ERROR STRING: " << p->errorString();
}
QString s = QString(p->readAll() + p->readAllStandardOutput());
return s;
}
else{
qDebug() << "waitForStarted() [false] : CODE: " << QVariant(p->error()).toString() << " | ERROR STRING: " << p->errorString();
}
p->waitForFinished();
p->kill();
return QString();
}
流程的终端输出：
started
readChannelFinished
exit code = "0"
waitForReadyRead() [false] : CODE: "5" | ERROR STRING: "Unknown error"
""
waitForFinished() [false] : CODE: "5" | ERROR STRING: "Unknown error"
Press <RETURN> to close this window...
对此有何想法？
更新2
@塔罗德感谢您花时间制定解决方案。
它工作，但不完全是预期的。
我完全抄袭了你的代码。
在mReadyReadStandardOutput()做了一些更改
请参阅以下其他信息。
问题：
运行应用程序（和脚本）后，我得到一个结果 - >真棒
每次它是不正确的结果，即“失败”。 - >不是真的
终端输出：
void MyProcess::myReadyRead()
void MyProcess::myReadyReadStandardOutput()
"enter your name:n"
""
void MyProcess::myReadyRead()
void MyProcess::myReadyReadStandardOutput()
"failedn"
Press <RETURN> to close this window...
脚本内容：
#!/bin/bash
echo "enter your name:"
read n
echo $n > "/tmp/log_test.txt"
if [[ ! -z "$n" ]];
then
echo "success"
exit 0;
else
echo "failed"
exit 1;
fi
/tmp/log_test.txt输出
myname
从控制台手动运行此操作：
dev@dev-W55xEU:~$ ls -la script
-rwxrwxr-x 1 dev dev 155 Jan 25 14:53 script*
dev@dev-W55xEU:~$ ./script
enter your name:
TEST_NAME
success
dev@dev-W55xEU:~$ cat /tmp/log_test.txt
TEST_NAME
完整代码：
#include <QCoreApplication>
#include <QProcess>
#include <QDebug>
class MyProcess : public QProcess
{
Q_OBJECT
public:
MyProcess(QObject *parent = 0);
~MyProcess() {}
public slots:
void myReadyRead();
void myReadyReadStandardOutput();
};
MyProcess::MyProcess(QObject *parent)
{
connect(this,SIGNAL(readyRead()),
this,SLOT(myReadyRead()));
connect(this,SIGNAL(readyReadStandardOutput()),
this,SLOT(myReadyReadStandardOutput()));
}
void MyProcess::myReadyRead() {
qDebug() << Q_FUNC_INFO;
}
void MyProcess::myReadyReadStandardOutput() {
qDebug() << Q_FUNC_INFO;
// Note we need to add n (it's like pressing enter key)
QString s = this->readAllStandardOutput();
qDebug() << s;
if (s.contains("enter your name")) {
this->write(QString("myname" + QString("n")).toLatin1());
qDebug() << this->readAllStandardOutput();
}
}
int main(int argc, char *argv[])
{
QCoreApplication a(argc, argv);
MyProcess *myProcess = new MyProcess();
QString program = "/home/dev/script";
myProcess->start("/bin/sh", QStringList() << program);
a.exec();
}
#include "main.moc"
脚本问题？ QProcess问题？
不幸的是我没有你所有的代码，所以我举了一个例子。 我希望它能帮助你。
如果我将自己的代码与您的代码进行比较，我认为问题可能在于您没有在写入之后调用readAllStandardOutput() ，也可能没有在main.cpp中调用exec() 。
#include <QCoreApplication>
#include <QProcess>
#include <QDebug>
class MyProcess : public QProcess
{
Q_OBJECT
public:
MyProcess(QObject *parent = 0);
~MyProcess() {}
public slots:
void myReadyRead();
void myReadyReadStandardOutput();
};
MyProcess::MyProcess(QObject *parent)
{
connect(this,SIGNAL(readyRead()),
this,SLOT(myReadyRead()));
connect(this,SIGNAL(readyReadStandardOutput()),
this,SLOT(myReadyReadStandardOutput()));
}
void MyProcess::myReadyRead() {
qDebug() << Q_FUNC_INFO;
}
void MyProcess::myReadyReadStandardOutput() {
qDebug() << Q_FUNC_INFO;
// Note we need to add n (it's like pressing enter key)
this->write(QString("myname" + QString("n")).toLatin1());
// Next line no required
// qDebug() << this->readAll();
qDebug() << this->readAllStandardOutput();
}
int main(int argc, char *argv[])
{
QCoreApplication a(argc, argv);
MyProcess *myProcess = new MyProcess();
QString program = "/home/fran/code/myscript.sh";
myProcess->start("/bin/sh", QStringList() << program);
a.exec();
}
#include "main.moc"
测试应用程序的脚本：
echo "enter your name:"
read n
if [ ! -z "$n" ];
then
echo "success"
exit 0;
else
echo "failed"
exit 1;
fi
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