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This class contains a set of options for launching child processes, such as where its standard input and output will be directed, the argument list, the environment, and more.
While the GSubprocess class has high level functions covering popular cases, use of this class allows access to more advanced options. It can also be used to launch multiple subprocesses with a similar configuration.
GSubprocessLauncher *
g_subprocess_launcher_new (GSubprocessFlags flags
);
Creates a new GSubprocessLauncher.
The launcher is created with the default options. A copy of the environment of the calling process is made at the time of this call and will be used as the environment that the process is launched in.
Since 2.40
GSubprocess * g_subprocess_launcher_spawn (GSubprocessLauncher *self
,GError **error
,const gchar *argv0
,...
);
Creates a GSubprocess given a provided varargs list of arguments.
Since 2.40
GSubprocess * g_subprocess_launcher_spawnv (GSubprocessLauncher *self
,const gchar * const *argv
,GError **error
);
Creates a GSubprocess given a provided array of arguments.
self |
||
argv |
Command line arguments. |
[array zero-terminated=1][element-type utf8] |
error |
Error |
Since 2.40
void g_subprocess_launcher_set_environ (GSubprocessLauncher *self
,gchar **env
);
Replace the entire environment of processes launched from this launcher with the given 'environ' variable.
Typically you will build this variable by using g_listenv()
to copy
the process 'environ' and using the functions g_environ_setenv()
,
g_environ_unsetenv()
, etc.
As an alternative, you can use g_subprocess_launcher_setenv()
,
g_subprocess_launcher_unsetenv()
, etc.
All strings in this array are expected to be in the GLib file name encoding. On UNIX, this means that they can be arbitrary byte strings. On Windows, they should be in UTF-8.
Since 2.40
void g_subprocess_launcher_setenv (GSubprocessLauncher *self
,const gchar *variable
,const gchar *value
,gboolean overwrite
);
Sets the environment variable variable
in the environment of
processes launched from this launcher.
Both the variable's name and value should be in the GLib file name encoding. On UNIX, this means that they can be arbitrary byte strings. On Windows, they should be in UTF-8.
self |
||
variable |
the environment variable to set, must not contain '=' |
|
value |
the new value for the variable |
|
overwrite |
whether to change the variable if it already exists |
Since 2.40
void g_subprocess_launcher_unsetenv (GSubprocessLauncher *self
,const gchar *variable
);
Removes the environment variable variable
from the environment of
processes launched from this launcher.
The variable name should be in the GLib file name encoding. On UNIX, this means that they can be arbitrary byte strings. On Windows, they should be in UTF-8.
Since 2.40
const gchar * g_subprocess_launcher_getenv (GSubprocessLauncher *self
,const gchar *variable
);
Returns the value of the environment variable variable
in the
environment of processes launched from this launcher.
The returned string is in the GLib file name encoding. On UNIX, this means that it can be an arbitrary byte string. On Windows, it will be UTF-8.
Since 2.40
void g_subprocess_launcher_set_cwd (GSubprocessLauncher *self
,const gchar *cwd
);
Sets the current working directory that processes will be launched with.
By default processes are launched with the current working directory of the launching process at the time of launch.
Since 2.40
void g_subprocess_launcher_set_flags (GSubprocessLauncher *self
,GSubprocessFlags flags
);
Sets the flags on the launcher.
The default flags are G_SUBPROCESS_FLAGS_NONE
.
You may not set flags that specify conflicting options for how to
handle a particular stdio stream (eg: specifying both
G_SUBPROCESS_FLAGS_STDIN_PIPE
and
G_SUBPROCESS_FLAGS_STDIN_INHERIT
).
You may also not set a flag that conflicts with a previous call to a
function like g_subprocess_launcher_set_stdin_file_path()
or
g_subprocess_launcher_take_stdout_fd()
.
Since 2.40
void g_subprocess_launcher_set_stdin_file_path (GSubprocessLauncher *self
,const gchar *path
);
Sets the file path to use as the stdin for spawned processes.
If path
is NULL
then any previously given path is unset.
The file must exist or spawning the process will fail.
You may not set a stdin file path if a stdin fd is already set or if the launcher flags contain any flags directing stdin elsewhere.
This feature is only available on UNIX.
Since 2.40
void g_subprocess_launcher_take_stdin_fd (GSubprocessLauncher *self
,gint fd
);
Sets the file descriptor to use as the stdin for spawned processes.
If fd
is -1 then any previously given fd is unset.
Note that if your intention is to have the stdin of the calling
process inherited by the child then G_SUBPROCESS_FLAGS_STDIN_INHERIT
is a better way to go about doing that.
The passed fd
is noted but will not be touched in the current
process. It is therefore necessary that it be kept open by the
caller until the subprocess is spawned. The file descriptor will
also not be explicitly closed on the child side, so it must be marked
O_CLOEXEC if that's what you want.
You may not set a stdin fd if a stdin file path is already set or if the launcher flags contain any flags directing stdin elsewhere.
This feature is only available on UNIX.
Since 2.40
void g_subprocess_launcher_set_stdout_file_path (GSubprocessLauncher *self
,const gchar *path
);
Sets the file path to use as the stdout for spawned processes.
If path
is NULL
then any previously given path is unset.
The file will be created or truncated when the process is spawned, as would be the case if using '>' at the shell.
You may not set a stdout file path if a stdout fd is already set or if the launcher flags contain any flags directing stdout elsewhere.
This feature is only available on UNIX.
Since 2.40
void g_subprocess_launcher_take_stdout_fd (GSubprocessLauncher *self
,gint fd
);
Sets the file descriptor to use as the stdout for spawned processes.
If fd
is -1 then any previously given fd is unset.
Note that the default behaviour is to pass stdout through to the stdout of the parent process.
The passed fd
is noted but will not be touched in the current
process. It is therefore necessary that it be kept open by the
caller until the subprocess is spawned. The file descriptor will
also not be explicitly closed on the child side, so it must be marked
O_CLOEXEC if that's what you want.
You may not set a stdout fd if a stdout file path is already set or if the launcher flags contain any flags directing stdout elsewhere.
This feature is only available on UNIX.
Since 2.40
void g_subprocess_launcher_set_stderr_file_path (GSubprocessLauncher *self
,const gchar *path
);
Sets the file path to use as the stderr for spawned processes.
If path
is NULL
then any previously given path is unset.
The file will be created or truncated when the process is spawned, as would be the case if using '2>' at the shell.
If you want to send both stdout and stderr to the same file then use
G_SUBPROCESS_FLAGS_STDERR_MERGE
.
You may not set a stderr file path if a stderr fd is already set or if the launcher flags contain any flags directing stderr elsewhere.
This feature is only available on UNIX.
Since 2.40
void g_subprocess_launcher_take_stderr_fd (GSubprocessLauncher *self
,gint fd
);
Sets the file descriptor to use as the stderr for spawned processes.
If fd
is -1 then any previously given fd is unset.
Note that the default behaviour is to pass stderr through to the stderr of the parent process.
The passed fd
belongs to the GSubprocessLauncher. It will be
automatically closed when the launcher is finalized. The file
descriptor will also be closed on the child side when executing the
spawned process.
You may not set a stderr fd if a stderr file path is already set or if the launcher flags contain any flags directing stderr elsewhere.
This feature is only available on UNIX.
Since 2.40
void g_subprocess_launcher_take_fd (GSubprocessLauncher *self
,gint source_fd
,gint target_fd
);
Transfer an arbitrary file descriptor from parent process to the
child. This function takes "ownership" of the fd; it will be closed
in the parent when self
is freed.
By default, all file descriptors from the parent will be closed.
This function allows you to create (for example) a custom pipe()
or
socketpair()
before launching the process, and choose the target
descriptor in the child.
An example use case is GNUPG, which has a command line argument --passphrase-fd providing a file descriptor number where it expects the passphrase to be written.
void g_subprocess_launcher_set_child_setup (GSubprocessLauncher *self
,GSpawnChildSetupFunc child_setup
,gpointer user_data
,GDestroyNotify destroy_notify
);
Sets up a child setup function.
The child setup function will be called after fork()
but before
exec()
on the child's side.
destroy_notify
will not be automatically called on the child's side
of the fork()
. It will only be called when the last reference on the
GSubprocessLauncher is dropped or when a new child setup function is
given.
NULL
can be given as child_setup
to disable the functionality.
Child setup functions are only available on UNIX.
self |
||
child_setup |
a GSpawnChildSetupFunc to use as the child setup function |
|
user_data |
user data for |
|
destroy_notify |
a GDestroyNotify for |
Since 2.40
“flags”
property“flags” GSubprocessFlags
GSubprocessFlags for launched processes.
Flags: Write / Construct Only