QtBase  v6.3.1
src_corelib_io_qiodevice.cpp
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50 
52 QProcess gzip;
53 gzip.start("gzip", QStringList() << "-c");
54 if (!gzip.waitForStarted())
55  return false;
56 
57 gzip.write("uncompressed data");
58 
60 while (gzip.waitForReadyRead())
61  compressed += gzip.readAll();
63 
64 
66 qint64 CustomDevice::bytesAvailable() const
67 {
68  return buffer.size() + QIODevice::bytesAvailable();
69 }
71 
72 
74 QFile file("box.txt");
76  char buf[1024];
77  qint64 lineLength = file.readLine(buf, sizeof(buf));
78  if (lineLength != -1) {
79  // the line is available in buf
80  }
81 }
83 
84 
86 bool CustomDevice::canReadLine() const
87 {
88  return buffer.contains('\n') || QIODevice::canReadLine();
89 }
91 
92 
95 {
96  char buf[2];
97  if (file->peek(buf, sizeof(buf)) == sizeof(buf))
98  return (buf[0] == 'M' && buf[1] == 'Z');
99  return false;
100 }
102 
103 
105 bool isExeFile(QFile *file)
106 {
107  return file->peek(2) == "MZ";
108 }
The QByteArray class provides an array of bytes.
Definition: qbytearray.h:85
The QFile class provides an interface for reading from and writing to files.
Definition: qfile.h:94
bool open(OpenMode flags) override
Definition: qfile.cpp:897
qint64 readLine(char *data, qint64 maxlen)
Definition: qiodevice.cpp:1356
qint64 peek(char *data, qint64 maxlen)
Definition: qiodevice.cpp:1922
virtual qint64 bytesAvailable() const
Definition: qiodevice.cpp:995
virtual bool canReadLine() const
Definition: qiodevice.cpp:1581
QList< QString > QStringList
Definition: qcontainerfwd.h:64
long long qint64
Definition: qglobal.h:298
GLenum GLuint buffer
GLenum GLuint GLenum GLsizei const GLchar * buf
bool isExeFile(QFile *file)
[3]
QProcess gzip
[0]
QByteArray compressed
QFile file("box.txt")
[1]