Class
GioApplicationCommandLine
Description [src]
class Gio.ApplicationCommandLine : GObject.Object
{
/* No available fields */
}
GApplicationCommandLine
represents a command-line invocation of
an application.
It is created by GApplication
and emitted
in the GApplication::command-line
signal and virtual function.
The class contains the list of arguments that the program was invoked with. It is also possible to query if the commandline invocation was local (ie: the current process is running in direct response to the invocation) or remote (ie: some other process forwarded the commandline to this process).
The GApplicationCommandLine
object can provide the argc
and argv
parameters for use with the GOptionContext
command-line parsing API,
with the g_application_command_line_get_arguments()
function. See
[gapplication-example-cmdline3.c][gapplication-example-cmdline3]
for an example.
The exit status of the originally-invoked process may be set and messages can be printed to stdout or stderr of that process.
For remote invocation, the originally-invoked process exits when
g_application_command_line_done()
method is called. This method is
also automatically called when the object is disposed.
The main use for GApplicationCommandLine
(and the
GApplication::command-line
signal) is ‘Emacs server’ like use cases:
You can set the EDITOR
environment variable to have e.g. git use
your favourite editor to edit commit messages, and if you already
have an instance of the editor running, the editing will happen
in the running instance, instead of opening a new one. An important
aspect of this use case is that the process that gets started by git
does not return until the editing is done.
Normally, the commandline is completely handled in the
GApplication::command-line
handler. The launching instance exits
once the signal handler in the primary instance has returned, and
the return value of the signal handler becomes the exit status
of the launching instance.
static int
command_line (GApplication *application,
GApplicationCommandLine *cmdline)
{
gchar **argv;
gint argc;
gint i;
argv = g_application_command_line_get_arguments (cmdline, &argc);
g_application_command_line_print (cmdline,
"This text is written back\n"
"to stdout of the caller\n");
for (i = 0; i < argc; i++)
g_print ("argument %d: %s\n", i, argv[i]);
g_strfreev (argv);
return 0;
}
The complete example can be found here: gapplication-example-cmdline.c
In more complicated cases, the handling of the commandline can be split between the launcher and the primary instance.
static gboolean
test_local_cmdline (GApplication *application,
gchar ***arguments,
gint *exit_status)
{
gint i, j;
gchar **argv;
argv = *arguments;
if (argv[0] == NULL)
{
*exit_status = 0;
return FALSE;
}
i = 1;
while (argv[i])
{
if (g_str_has_prefix (argv[i], "--local-"))
{
g_print ("handling argument %s locally\n", argv[i]);
g_free (argv[i]);
for (j = i; argv[j]; j++)
argv[j] = argv[j + 1];
}
else
{
g_print ("not handling argument %s locally\n", argv[i]);
i++;
}
}
*exit_status = 0;
return FALSE;
}
static void
test_application_class_init (TestApplicationClass *class)
{
G_APPLICATION_CLASS (class)->local_command_line = test_local_cmdline;
...
}
In this example of split commandline handling, options that start
with --local-
are handled locally, all other options are passed
to the GApplication::command-line
handler which runs in the primary instance.
The complete example can be found here: gapplication-example-cmdline2.c
If handling the commandline requires a lot of work, it may be better to defer it.
static gboolean
my_cmdline_handler (gpointer data)
{
GApplicationCommandLine *cmdline = data;
// do the heavy lifting in an idle
g_application_command_line_set_exit_status (cmdline, 0);
g_object_unref (cmdline); // this releases the application
return G_SOURCE_REMOVE;
}
static int
command_line (GApplication *application,
GApplicationCommandLine *cmdline)
{
// keep the application running until we are done with this commandline
g_application_hold (application);
g_object_set_data_full (G_OBJECT (cmdline),
"application", application,
(GDestroyNotify)g_application_release);
g_object_ref (cmdline);
g_idle_add (my_cmdline_handler, cmdline);
return 0;
}
In this example the commandline is not completely handled before
the GApplication::command-line
handler returns. Instead, we keep
a reference to the GApplicationCommandLine
object and handle it
later (in this example, in an idle). Note that it is necessary to
hold the application until you are done with the commandline.
The complete example can be found here: gapplication-example-cmdline3.c
Instance methods
g_application_command_line_create_file_for_arg
Creates a GFile
corresponding to a filename that was given as part
of the invocation of cmdline
.
since: 2.36
g_application_command_line_get_arguments
Gets the list of arguments that was passed on the command line.
since: 2.28
g_application_command_line_get_cwd
Gets the working directory of the command line invocation. The string may contain non-utf8 data.
since: 2.28
g_application_command_line_get_environ
Gets the contents of the ‘environ’ variable of the command line
invocation, as would be returned by g_get_environ(), ie as a
NULL
-terminated list of strings in the form ‘NAME=VALUE’.
The strings may contain non-utf8 data.
since: 2.28
g_application_command_line_get_exit_status
Gets the exit status of cmdline
. See
g_application_command_line_set_exit_status()
for more information.
since: 2.28
g_application_command_line_get_is_remote
Determines if cmdline
represents a remote invocation.
since: 2.28
g_application_command_line_get_options_dict
Gets the options that were passed to g_application_command_line().
since: 2.40
g_application_command_line_get_platform_data
Gets the platform data associated with the invocation of cmdline
.
since: 2.28
g_application_command_line_getenv
Gets the value of a particular environment variable of the command line invocation, as would be returned by g_getenv(). The strings may contain non-utf8 data.
since: 2.28
g_application_command_line_print
Formats a message and prints it using the stdout print handler in the invoking process.
since: 2.28
g_application_command_line_print_literal
Prints a message using the stdout print handler in the invoking process.
since: 2.80
g_application_command_line_printerr
Formats a message and prints it using the stderr print handler in the invoking process.
since: 2.28
g_application_command_line_printerr_literal
Prints a message using the stderr print handler in the invoking process.
since: 2.80
g_application_command_line_set_exit_status
Sets the exit status that will be used when the invoking process exits.
since: 2.28
Properties
Gio.ApplicationCommandLine:arguments
The commandline that caused this GApplication::command-line
signal emission.
since: 2.28
Signals
Signals inherited from GObject (1)
GObject::notify
The notify signal is emitted on an object when one of its properties has its value set through g_object_set_property(), g_object_set(), et al.
Class structure
struct GioApplicationCommandLineClass {
void (* print_literal) (
GApplicationCommandLine* cmdline,
const gchar* message
);
void (* printerr_literal) (
GApplicationCommandLine* cmdline,
const gchar* message
);
GInputStream* (* get_stdin) (
GApplicationCommandLine* cmdline
);
void (* done) (
GApplicationCommandLine* cmdline
);
}
The GApplicationCommandLineClass
-struct
contains private data only.
Class members
print_literal: void (* print_literal) ( GApplicationCommandLine* cmdline, const gchar* message )
- No description available.
printerr_literal: void (* printerr_literal) ( GApplicationCommandLine* cmdline, const gchar* message )
- No description available.
get_stdin: GInputStream* (* get_stdin) ( GApplicationCommandLine* cmdline )
- No description available.
done: void (* done) ( GApplicationCommandLine* cmdline )
- No description available.
Virtual methods
Gio.ApplicationCommandLineClass.print_literal
Prints a message using the stdout print handler in the invoking process.
since: 2.80
Gio.ApplicationCommandLineClass.printerr_literal
Prints a message using the stderr print handler in the invoking process.
since: 2.80