CHIPMAKER

/*
* main.c -- C Test App.
*
* Copyright (C) 2012-2013, 2013 heesoon.kim <chipmaker.tistory.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <limits.h>
#include <errno.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <time.h>
#include <sys/types.h>
#include <sys/select.h>

#define MAX_BUFFER_LEN 256

int main(int argc, char *argv[])
{
	int retval, n;
	int fd;
	fd_set readfds, writefd;
	char buffer[MAX_BUFFER_LEN];
	
	if((fd = open("./temp.txt", O_RDONLY)) == -1)
	{
		perror("open : ");
		exit(EXIT_FAILURE);
	}

/*	
	newfd = dup(STDOUT_FILENO);
	if(newfd == -1)
	{
		perror("dup : ");
		exit(EXIT_FAILURE);	
	}
	
	close(STDOUT_FILENO);
*/	
	while(1)
	{
		FD_ZERO(&readfds);
		FD_ZERO(&writefd);
		FD_SET(fd, &readfds);
		
		retval = select(fd + 1, &readfds, &writefd, NULL, NULL);

		switch(retval)
		{
			case -1:
				perror("slect : ");
				exit(EXIT_FAILURE);
			
			default :
				if(FD_ISSET(fd, &readfds))
				{
					while((n = read(fd, buffer, MAX_BUFFER_LEN)) > 0)
					{
						printf("%s", buffer);
					}
				}
				
				memset(buffer, 0, MAX_BUFFER_LEN);
				break;
		}
		
		usleep(1000);
	}
	
	close(fd);
	exit(EXIT_SUCCESS);
}

/*
* main.c -- C Test App.
*
* Copyright (C) 2012-2013, 2013 heesoon.kim <chipmaker.tistory.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <time.h>

int main(int argc, char *argv[])
{
	time_t t;
	struct stat statbuf;

	if(stat("./main.c", &statbuf) == -1)
	{
		perror("fopen");
		exit(EXIT_FAILURE);	
	}
	
	// major/minor number print
	printf("major = %ld\n", major(statbuf.st_dev));
	printf("minor = %ld\n", minor(statbuf.st_dev));
	
	// file total size print
	printf("file size = %ld \n", statbuf.st_size);
	
	// file modify time print
	t = statbuf.st_mtime;
	printf("%s\n", ctime(&t));

	// file mode check, the macro is defined to <sys/stat.h>
	//if((statbuf.st_mode & S_IFMT) == S_IFREG)
	if(S_ISREG(statbuf.st_mode))
		printf("regular file\n");
	
	exit(EXIT_SUCCESS);
}

/*
* main.c -- C Test App.
*
* Copyright (C) 2012-2013, 2013 heesoon.kim <chipmaker.tistory.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <errno.h>

int main(int argc, char *argv[])
{
	pid_t pid, wpid;
	int status;
	
	pid = fork();

	switch(pid)
	{
		case -1: 
			_exit(EXIT_FAILURE);
			
		case 0 : // child process
			printf("child process call fork() fucntion \n");
			_exit(EXIT_SUCCESS);

		default: // parent process
			wait(&status);
			printf("child process exit status = %d \n", WEXITSTATUS(status));
			break;
	}
	
	exit(EXIT_SUCCESS);
}

/*
* main.c -- C Test App.
*
* Copyright (C) 2012-2013, 2013 heesoon.kim <chipmaker.tistory.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <sys/time.h>
#include <time.h>

static void signal_handler(int sig)
{
	printf("%s : signal received \n", strsignal(sig));
	
}

int main(int argc, char *argv[])
{
	int retval = -1;
	struct sigaction sa;
	struct itimerval itv = {0};
	struct itimerval curitv = {0};
	
	itv.it_interval.tv_sec = 2;
	itv.it_value.tv_sec = 2;
	
	sigemptyset(&sa.sa_mask);
	sa.sa_handler = signal_handler;
	//sa.sa_flags = SA_RESETHAND;
	if(sigaction(SIGALRM, &sa, NULL) == -1)
		perror("sigaction");
	
 	printf("START Timer \n");
	
	setitimer(ITIMER_REAL, &itv, NULL);
	//alarm(2);
	while(1)
	{	
		if(getitimer(ITIMER_REAL, &curitv) == -1)
		{
			perror("getitimer");
			break;
		}
		printf("Remained secs : %ld\n", curitv.it_value.tv_sec);
		sleep(1);
	}
	
	printf("End Timer \n");
	return 0;
}

*
* main.c -- C Test App.
*
* Copyright (C) 2012-2013, 2013 heesoon.kim <chipmaker.tistory.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <sys/time.h>
#include <time.h>

int main(int argc, char *argv[])
{
	struct timeval tv;
	time_t t;
	
	if(gettimeofday(&tv, NULL) == -1)
		perror("gettimeofday\n");
	
	printf("gettimeofday = %ld, %ld\n", tv.tv_sec, tv.tv_usec);
	
	t = time(NULL);
	if(errno == EFAULT)
		perror("time\n");
	
	printf("time = %ld\n", t);	
	
	printf("current time : %s", ctime(&t));
	printf("current time : %s", ctime(&tv.tv_sec));
	
	return 0;
}

/*
* main.c -- C Test App.
*
* Copyright (C) 2012-2013, 2013 heesoon.kim <chipmaker.tistory.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <sys/time.h>
#include <time.h>

int main(int argc, char *argv[])
{
	struct tm *t;
	time_t tt;
	
	tt = time(NULL);
	if(errno == EFAULT)
		perror("time\n");

	// GMT Time
	t = gmtime(&tt);	
	printf("gmt time   : %s", asctime(t));
	
	// Local Time
	t = localtime(&tt);
	printf("local time : %s", asctime(t));
	
	return 0;
}

int flags;
	
flags = fcntl(fd, F_GETFL);
if(flags == -1)
	perror("fcntl");
	
if(flags & O_SYNC)
	printf("writes are synchronized\n");

accessMode = flags & O_ACCMODE;

if(accessMode == O_WRONLY || accessMode == O_RDWR)
	printf("file is writable\n");

int flags;

flags = fcntl(fd, F_GETFL);
if(flags == -1)
	perror("fcntl");

flags |= O_APPEND;
if(fcntl(fd, F_SETFL, flags) == -1)
	perror("fcntl");

/*
* main.c -- C Test App.
*
* Copyright (C) 2012-2013, 2013 heesoon.kim <chipmaker.tistory.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <signal.h>

void signal_handler(int sig)
{
	if(sig == SIGINT)
		printf("SIGINT is tranfered \n");
	
	if(sig == SIGQUIT)
	{
		printf("SIGQUIT is tranfered \n");
		exit(1);
	}
	
}

int main(int argc, char *argv[])
{
	if(signal(SIGINT, signal_handler) == SIG_ERR)
	{
		printf("signal error\n");
		exit(1);
	}

	if(signal(SIGQUIT, signal_handler) == SIG_ERR)
	//if(signal(SIGQUIT, SIG_DFL) == SIG_ERR)
	{
		printf("signal error\n");
		exit(1);
	}	
	
	//while(getchar() != 'q');
	for(;;)
	{
		printf("main function is paused, PID = %d \n", getpid());
		pause();
	}
	
	return 0;
}