ost::Process Class Reference

A class for containing portable process related functions that help create portable code. More...

#include <process.h>

Public Types
typedef void(*	Trap )(int)
Public Member Functions
bool	lock (bool future=true)
	Lock a process in memory.
void	unlock (void)
	Unlock process pages.
Static Public Member Functions
static void	attach (const char *devname)
	Attach the current process to another device or i/o session.
static bool	cancel (int pid, int sig=0)
	Cancel a running child process.
static void	detach (void)
	Detach current process into a daemon, posix only.
static const char *	getConfigDir (void)
	Get etc prefix path.
static const char *	getEnv (const char *name)
	Get system environment.
static const char *	getHomeDir (void)
	Get home directory.
static size_t	getPageSize (void)
	Return the effective operating system page size.
static const char *	getUser (void)
	Get user name.
static bool	isRealtime (void)
	Return true if realtime scheduling.
static bool	isScheduler (void)
	Return true if scheduler settable.
static int	join (int pid)
	Get the exit status of another process, waiting for it to exit.
static void	setEnv (const char *name, const char *value, bool overwrite)
	Set system environment in a standard manner.
static bool	setGroup (const char *id)
	Set the effective group id by name.
static Trap	setInterruptSignal (int signo, Trap handler)
	Set system call interuptable signal handler.
static Trap	setPosixSignal (int signo, Trap handler)
	Set a posix compliant signal handler.
static void	setPriority (int pri)
	Used to set process priority and optionally enable realtime.
static void	setRealtime (int pri=0)
	Portable shortcut for setting realtime.
static void	setScheduler (const char *policy)
	Used to set process scheduling policy.
static bool	setUser (const char *id, bool grp=true)
	Set user id by name.
static int	spawn (const char *exec, const char **argv, bool wait=true)
	Spawn a process and wait for it's exit code.

---

Detailed Description

A class for containing portable process related functions that help create portable code.

These are typically referenced thru Process::xxx static member functions. Many of these members are used both for win32 and posix systems although some may be platform specific.

Peocess wrapper class.

Author:

David Sugar <dyfet@ostel.com>

Definition at line 66 of file process.h.

---

Member Function Documentation

static void ost::Process::attach

(

const char *

devname

)

[static]

Attach the current process to another device or i/o session.

It is deamonified and dissasociated with the prior parent process and controlling terminal.

Parameters:

devname

path to attach to.

static bool ost::Process::cancel	(	int	pid,
		int	sig = 0
	)			[static]

Cancel a running child process.

Returns:

0 on success.

Parameters:

	pid	process id.
	sig	cancel signal to apply.

static void ost::Process::detach

(

void

)

[static]

Detach current process into a daemon, posix only.

Perhaps a similar method can be used for creating win32 "services"?

static const char* ost::Process::getConfigDir

(

void

)

[static]

Get etc prefix path.

Returns:

etc prefix.

static const char* ost::Process::getEnv

(

const char *

name

)

[static]

Get system environment.

Returns:

system environ symbol.

Parameters:

name

of symbol.

static const char* ost::Process::getHomeDir

(

void

)

[static]

Get home directory.

Returns:

user home directory.

static size_t ost::Process::getPageSize

(

void

)

[static]

Return the effective operating system page size.

Returns:

system page size.

static const char* ost::Process::getUser

(

void

)

[static]

Get user name.

Returns:

user login id.

static int ost::Process::join

(

int

pid

)

[static]

Get the exit status of another process, waiting for it to exit.

Returns:

exit code from process.

Parameters:

pid

process id.

bool ost::Process::lock

(

bool

future = true

)

Lock a process in memory.

Ideally you should be deep enough where additional memallocs for functions will not kill you, or use false for future.

Returns:

true if successful.

Parameters:

future

pages as well...

static void ost::Process::setEnv	(	const char *	name,
		const char *	value,
		bool	overwrite
	)			[static]

Set system environment in a standard manner.

Parameters:

	name	of environment symbol to set.
	value	of environment symbol.
	overwrite	true if replace existing symbol.

static bool ost::Process::setGroup

(

const char *

id

)

[static]

Set the effective group id by name.

Returns:

true if successful.

static Trap ost::Process::setInterruptSignal	(	int	signo,
		Trap	handler
	)			[static]

Set system call interuptable signal handler.

return previous handler.

Parameters:

	signo	signal no.
	handler	trap handler.

static Trap ost::Process::setPosixSignal	(	int	signo,
		Trap	handler
	)			[static]

Set a posix compliant signal handler.

Returns:

previous handler.

Parameters:

	signo	signal no.
	handler	trap handler.

static void ost::Process::setRealtime

(

int

pri = 0

)

[static]

Portable shortcut for setting realtime.

..

static bool ost::Process::setUser	(	const char *	id,
		bool	grp = true
	)			[static]

Set user id by name.

Returns:

true if successful.

static int ost::Process::spawn	(	const char *	exec,
		const char **	argv,
		bool	wait = true
	)			[static]

Spawn a process and wait for it's exit code.

In win32 this is done with the spawn system call. In posix, this is done with a fork, an execvp, and a waitpid.

Warning:

The implementation differences between posix and win32 systems may cause side effects. For instance, if you use atexit() and this spawn method, on posix systems the function set up with atexit() will be called when the parent process of the fork exits, which will not happen on Win32 systems.

Returns:

error code from process.

Parameters:

	exec	name of executable.
	argv	list of command arguments.
	wait	for process to exit before return.

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The documentation for this class was generated from the following file:

• commoncpp/process.h