TCGETPGRP(3) - Linux man page online | Library functions
Get and set terminal foreground process group.
TCGETPGRP(3) Linux Programmer's Manual TCGETPGRP(3)
GNU 2015-08-08 TCGETPGRP(3)
NAMEtcgetpgrp, tcsetpgrp - get and set terminal foreground process group
SYNOPSIS#include <unistd.h> pid_t tcgetpgrp(int fd); int tcsetpgrp(int fd, pid_t pgrp);
DESCRIPTIONThe 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 mem‐ bers of this background process group.
RETURN VALUEWhen fd refers to the controlling terminal of the calling process, the function tcgetp‐ grp() 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 appropriately. When successful, tcsetpgrp() returns 0. Otherwise, it returns -1, and errno is set appro‐ priately.
ERRORSEBADF 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.
ATTRIBUTESFor an explanation of the terms used in this section, see attributes(7). ┌─────────────────────────┬───────────────┬─────────┐ │Interface │ Attribute │ Value │ ├─────────────────────────┼───────────────┼─────────┤ │tcgetpgrp(), tcsetpgrp() │ Thread safety │ MT-Safe │ └─────────────────────────┴───────────────┴─────────┘
CONFORMING TOPOSIX.1-2001, POSIX.1-2008.
NOTESThese functions are implemented via the TIOCGPGRP and TIOCSPGRP ioctls. History The ioctls appeared in 4.2BSD. The functions are POSIX inventions.
SEE ALSOsetpgid(2), setsid(2), credentials(7)
COLOPHONThis page is part of release 4.15 of the Linux man-pages project. A description of the project, information about reporting bugs, and the latest version of this page, can be found at https://www.kernel.org/doc/man-pages/.
|This manual||Reference||Other manuals|
|tcgetpgrp(3)||referred by||credentials(7) | fcntl(2freebsd) | procenv(1) | setpgid(2) | setsid(2freebsd) | signal-safety(7)|
|refer to||attributes(7) | credentials(7) | setpgid(2) | setsid(2)|