A simple implementation for tgkill

tgkill.c

#include <unistd.h>
#include <stdio.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <sys/signal.h>

#define ARRAY_SIZE(arr)    (sizeof(arr) / sizeof((arr)[0]))

// List common use signal names
static const struct signal_name {
	const char *name;
	int sig;
} signal_names[] = {
	{ "HUP",	SIGHUP },	
	{ "INT",	SIGINT },	
	{ "QUIT",	SIGQUIT },	
	{ "ILL",	SIGILL },	
	{ "TRAP",	SIGTRAP },	
	{ "ABRT",	SIGABRT },	
	{ "FPE",	SIGFPE },	
	{ "KILL",	SIGKILL },	
	{ "USR1",	SIGUSR1 },	 
	{ "SEGV",	SIGSEGV },	
	{ "USR2",	SIGUSR2 },	 
	{ "PIPE",	SIGPIPE },	
	{ "ALRM",	SIGALRM },	
	{ "TERM",	SIGTERM },	
	{ "CONT",	SIGCONT },
	{ "STOP",	SIGSTOP },
};

int signame_to_num(char *name) {
	size_t n;

	if(isdigit(*name)) {
		return atoi(name);
	}

	if(!strncasecmp(name, "sig", 3)) 
		name += 3;

	for(n = 0; n < ARRAY_SIZE(signal_names); n++) {
		if(!strncasecmp(signal_names[n].name, name)) {
			return signal_names[n].sig;
		}
	}

	return -1;
}

int main(int argc, char *argv[])
{
	int sig = SIGTERM;
	int tgid = -1;
	int tid;

	if (argc != 4) {
		printf("Usage: %s SIGNAL|SIGNUM <tgid> <tid>\n", argv[0]);
		return 1;
	} 

	sig = signame_to_num(argv[1]);
	tgid = atoi(argv[2]);
	tid = atoi(argv[3]);
	
	return syscall(SYS_tgkill, tgid, tid, sig);
}