Ordfoss

SingleInstance.h header

#include <ew/app/SingleInstance.h>

Namespace ew::app

LaunchArguments struct

struct ew::app::LaunchArguments

The forwarding-relevant parts of a command line, extracted from arguments (which includes the program name at index 0, as QCoreApplication::arguments() does).

Members

QString ew::app::workspace::LaunchArguments::projectPath

The positional project path (a double-clicked .ewriter file or a folder path), or empty.

bool ew::app::workspace::LaunchArguments::newInstance = false

True when --new-instance was passed: skip forwarding and always open a standalone window (so several projects can be worked side by side).

LaunchMessage struct

struct ew::app::LaunchMessage

A launch request forwarded from a second process to the already-running instance: a project to open, or – when the path is empty – just a nudge to raise the existing window (a bare second launch). One request is one UTF-8 line on the wire.

Members

QString ew::app::workspace::LaunchMessage::projectPath

The absolute project path to open; empty means "just raise the running window".

bool operator==(const LaunchMessage &, const LaunchMessage &)=default

Two messages are equal when they carry the same path.

Functions

LaunchMessage ew::app::workspace::decodeLaunchMessage(const QByteArray &bytes)

Decodes wire bytes back to a launch message, reading only the first line and tolerating a trailing CR/LF – so a partial or line-buffered read that ends the line decodes correctly.

QByteArray ew::app::workspace::encodeLaunchMessage(const LaunchMessage &message)

Encodes message to its wire bytes: the project path as one newline-terminated UTF-8 line (a path never contains a newline, so the line is unambiguous).

LaunchArguments ew::app::workspace::parseLaunchArguments(const QStringList &arguments)

Parses arguments for the project path and the --new-instance flag. --capture and --lang each consume the following argument as their value; any other --flag is ignored as a valueless option; the first remaining positional argument is the project path.

QString ew::app::workspace::singleInstanceServerName(const QString &userName)

The name of the per-user single-instance IPC channel (a QLocalServer pipe name). The desktop app's first process listens on this name; a second launch connects to it to forward its request instead of opening another window.

Two accounts on one machine never collide. That matters because a pipe name is machine-global on Windows, so a shared channel would forward one user's "open this project" into another user's window. The readable part of the name is the user name reduced to the characters a local-socket name safely allows – a lossy fold, which alone would make "J Smith" and "J_Smith" the same channel – so the name also carries a hash of the ORIGINAL userName, which distinguishes any two distinct names. The readable part is truncated, keeping the whole name within the OS limit for a long account name.