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System Calls - Manual Reference Pages  - TKILL (2)

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tkill - send a signal to a single process

CONTENTS

Synopsis
Description
Errors
Versions

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#include <sys/types.h> 

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#include <linux/unistd.h> 

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#include <errno.h> 



_syscall2(int, tkill, int, tid, int, sig) 
          /* Using syscall(2) may be preferable; see intro(2) */



int tkill(int tid, int sig); 

The tkill() system call is analogous to kill(2), except when the specified process is part of a thread group (created by specifying the CLONE_THREAD flag in the call to clone). Since all the processes in a thread group have the same PID, they cannot be individually signalled with kill(). With tkill(), however, one can address each process by its unique TID.

These are the raw system call interfaces, meant for internal thread library use.

On success, zero is returned. On error, -1 is returned, and errno is set appropriately.

EINVAL	An invalid TID or signal was specified.
EPERM	Permission denied. For the required permissions, see kill(2).
ESRCH	No process with the specified thread ID (and thread group ID) exists.

tkill() is Linux specific and should not be used in programs that are intended to be portable.

tkill() is supported since Linux 2.4.19 / 2.5.4.

gettid(2), kill(2), tgkill(2) or go to Top of page |  Section 2 |  Main Man Index.