получить и установить группу процессов переднего плана терминала (get and set terminal foreground process group)
Имя (Name)
tcgetpgrp, tcsetpgrp - get and set terminal foreground process
group
Синопсис (Synopsis)
#include <unistd.h>
pid_t tcgetpgrp(int
fd);
int tcsetpgrp(int
fd, pid_t
pgrp);
Описание (Description)
The function tcgetpgrp
() returns the process group ID of the
foreground process group on the terminal associated to fd, which
must be the controlling terminal of the calling process.
The function tcsetpgrp
() makes the process group with process
group ID pgrp the foreground process group on the terminal
associated to fd, which must be the controlling terminal of the
calling process, and still be associated with its session.
Moreover, pgrp must be a (nonempty) process group belonging to
the same session as the calling process.
If tcsetpgrp
() is called by a member of a background process
group in its session, and the calling process is not blocking or
ignoring SIGTTOU
, a SIGTTOU
signal is sent to all members of this
background process group.
Возвращаемое значение (Return value)
When fd refers to the controlling terminal of the calling
process, the function tcgetpgrp
() will return the foreground
process group ID of that terminal if there is one, and some value
larger than 1 that is not presently a process group ID otherwise.
When fd does not refer to the controlling terminal of the calling
process, -1 is returned, and errno is set to indicate the error.
When successful, tcsetpgrp
() returns 0. Otherwise, it returns
-1, and errno is set to indicate the error.
Ошибки (Error)
EBADF
fd is not a valid file descriptor.
EINVAL
pgrp has an unsupported value.
ENOTTY
The calling process does not have a controlling terminal,
or it has one but it is not described by fd, or, for
tcsetpgrp
(), this controlling terminal is no longer
associated with the session of the calling process.
EPERM
pgrp has a supported value, but is not the process group
ID of a process in the same session as the calling
process.
Атрибуты (Attributes)
For an explanation of the terms used in this section, see
attributes(7).
┌──────────────────────────────────────┬───────────────┬─────────┐
│Interface
│ Attribute
│ Value
│
├──────────────────────────────────────┼───────────────┼─────────┤
│tcgetpgrp
(), tcsetpgrp
() │ Thread safety │ MT-Safe │
└──────────────────────────────────────┴───────────────┴─────────┘
Стандарты (Conforming to)
POSIX.1-2001, POSIX.1-2008.
Примечание (Note)
These functions are implemented via the TIOCGPGRP
and TIOCSPGRP
ioctls.
History
The ioctls appeared in 4.2BSD. The functions are POSIX
inventions.
Смотри также (See also)
setpgid(2), setsid(2), credentials(7)