날짜,pthread,도메인

/*

strftime, strptime.

get_ip_cls

*/

#include <time.h>
int main(){
char buf[200] = "";
time_t now = 0;
struct tm *t = NULL;

//strftime.
now = time(NULL);
t = localtime(&now);
strftime(buf, 20, "%Y/%m/%d %H:%M:%S", t);
puts(buf);

//strptime.
strptime(buf, "%Y/%m/%d %H:%M:%S", &t);
sleep(3);
strftime(buf, 20, "%Y/%m/%d %H:%M:%S", t);
puts(buf);

return 0;
}

/*

날짜 관련 함수 예제

*/

#include "/home/jinyedge/lib/c/edgelib.h"

//-----------------
int main(void){
time_t now = 0;
struct tm *t = NULL;

/*오늘 날짜*/
now = time(NULL);
t = localtime(&now);
printf("%d-%02d-%02d\n" , t->tm_year + 1900, t->tm_mon + 1, t->tm_mday);

/*일주일전 날짜*/
now = time(NULL) - (86400 * 7);
t = localtime(&now);
printf("%d-%02d-%02d\n" , t->tm_year + 1900, t->tm_mon + 1, t->tm_mday);

/*한달전 날짜*/
now = time(NULL) - (86400 * 30);
t = localtime(&now);
printf("%d-%02d-%02d\n" , t->tm_year + 1900, t->tm_mon + 1, t->tm_mday);
}

/*

get_ip_cls

*/

//-----------------
char get_ip_cls(char *ip){
int i = 0, a = 0;
char buf[4] = "";
for(i = 0; i < strlen(ip); i++){
if(ip[i] == '.'){
buf[i] = '\0';
break;
}
buf[i] = ip[i];
}

a = atoi(buf);
if(a >= 0 && a <= 127){
return 'a';
}
else if(a >= 128 && a <= 191){
return 'b';
}
else if(a >= 192 && a <= 223){
return 'c';
}
else if(a >= 224 && a <= 239){
return 'd';
}
else{
return 'e';
}
}

//-----------------
int main(void){
printf("%c\n", get_ip_cls("192.168.10.10.1"));
return 0;
}

/*

ip_sub

*/

#include "/home/jinyedge/lib/c/edgelib.h"
//-----------------
unsigned long ip_sub(char *ip, char *ip2){
int i = 0, ip_no_arr[4] = {0, 0, 0, 0}, ip_no_arr2[4] = {0, 0, 0, 0}, k = 0;
unsigned long sum = 0;
List *list = NULL;

/*Get ip_no_arr*/
list = split(ip, ".");
for(i = 0; i < 4; i++){
ip_no_arr[i] = atoi(list->arr[i]);
}
list_free(list);

/*Get ip_no_arr2*/
list = split(ip2, ".");
for(i = 0; i < 4; i++){
ip_no_arr2[i] = atoi(list->arr[i]);
}
list_free(list);

/*Get res*/
sum = 0;
for(i = 0; i < 4; i++){
k = ip_no_arr[i] - ip_no_arr2[i];
if(i == 0){
sum += k * 255 * 255 * 255;
}
else if(i == 1){
sum += k * 255 * 255;
}
else if(i == 2){
sum += k * 255;
}
else if(i == 3){
sum += k;
}
}
return sum;
}

//-----------------
int main(void){
unsigned long res = 0;
char *ip = "192.168.10.1";
char *ip2 = "192.165.1.1";

res = ip_sub(ip, ip2);
printf("%u\n", res);
}

/*

get_time, get_date.

번호: 76 / 작성자: jinyedge / 등록일: 2004-06-27 22:13:05 / 조회: 115

*/ #include <stdio.h> #include <time.h> //----------------------- void get_time(char buf[]){ time_t now = 0; struct tm *t = NULL; now = time(NULL); t = localtime(&now); sprintf(buf, "%d/%02d/%02d %2d:%02d:%02d" , t->tm_year + 1900, t->tm_mon + 1, t->tm_mday, t->tm_hour, t->tm_min, t->tm_sec); } //----------------------- void get_date(char buf[]){ time_t now = 0; struct tm *t = NULL; now = time(NULL); t = localtime(&now); sprintf(buf, "%d/%02d/%02d", t->tm_year + 1900, t->tm_mon + 1, t->tm_mday); } //----------------------- int main(void){ char buf[1024]; get_date(buf); puts(buf); get_time(buf); puts(buf); return 0; }

/*

프로세스 읽기.

번호: 75 / 작성자: jinyedge / 등록일: 2004-06-27 21:58:10 / 조회: 141

*/ #include <stdio.h> #include <unistd.h> #define BUF_SIZE 8192 //----------------- int main(void){ FILE *fp = NULL; char buf[BUF_SIZE]; long rcnt = 0; if((fp = popen("ps -aux | grep '^root'", "r")) == NULL){return -1;} rcnt = fread(buf, sizeof(char), BUF_SIZE, fp); pclose(fp); printf("Read count: %d\n%s\n", rcnt, buf); return 0; }

/*

get_kw_q_part.

번호: 73 / 작성자: jinyedge / 등록일: 2003-08-24 19:22:44 / 조회: 166

*/ #include <stdio.h> #include <string.h> /*------------*/ void get_kw_q_part(char *arr[], int arr_len, char buf[]){ int i = 0; //If there's no arg. if(arr_len == 0){ strcpy(buf, ""); return; } //If there's only one arg. if(arr_len == 1){ sprintf(buf, "kw = '%s'", arr[0]); return; } //Append the args into buf. sprintf(buf, "kw in('%s'", arr[0]); for(i = 1; i < arr_len; i++){ sprintf(buf, "%s, '%s'", buf, arr[i]); } strcat(buf, ")"); } /*------------*/ int main(void){ char buf[1024]; char *arr[] = {"123", "456", "789"}; get_kw_q_part(arr, 1, buf); puts(buf); get_kw_q_part(arr, 3, buf); puts(buf); return 0; } /*

New substr functions.

번호: 72 / 작성자: jinyedge / 등록일: 2003-04-09 12:05:13 / 조회: 214

I realized I made some mistakes when I was writing substr functions using c. I think it was due to my lack of understanding of strncpy function. A few days ago I started studying c again to acquire some kind of certification. And it made me to realize my mistake which I made when I wrote substr functions that have taken important role in my library so far. So I wrote new version of my substr functions. */ /*-----------------------*/ /*스트링 자르기*/ void substr(char *line, int offset, int len, char buf[]){ if(len < 1 || offset >= (int)strlen(line)){ strcpy(buf, ""); return; } strncpy(buf, line + offset, len); buf[len] = '\0'; } /*-----------------------*/ /*스트링 자르기*/ void substr_nolen(char *line, int offset, char buf[]){ int str_len = 0, len = 0; str_len = (int)strlen(line); if(offset >= str_len){ strcpy(buf, ""); return; } len = str_len - offset; strncpy(buf, line + offset, len); buf[len] = '\0'; } /*-----------------------*/ char * psubstr(char *line, int offset, int len){/*스트링 자르기(스트링 포인터를 리턴한다.)*/ int str_len = 0; char *res = NULL; str_len = (int)strlen(line); if(len < 1 || offset >= str_len){return NULL;} /*Memory Size*/ if((offset + len) > str_len){len = str_len - offset;} res = (char *)malloc(sizeof(char) * (len + 1)); strncpy(res, line + offset, len); res[len] = '\0'; return res; } /*-----------------------*/ char * psubstr_nolen(char *line, int offset){/*스트링 자르기(스트링 포인터를 리턴한다.)*/ int str_len = 0, len = 0; char *res = NULL; str_len = (int)strlen(line); if(offset >= str_len){return NULL;} len = str_len - offset; /*Memory Size*/ res = (char *)malloc(sizeof(char) * (len + 1)); strncpy(res, line + offset, len); res[len] = '\0'; return res; } replace, replace_i 번호: 63 / 작성자: jinyedge / 등록일: 2002-05-28 13:01:14 / 조회: 192 #include <stdio.h> #include <stdlib.h> #include <string.h> #include <ctype.h> #include <time.h> /*-----------------------*/ void str_lower(char *line, char buf[]){/*스트링의 문자를 모두 소문자로 만든다.*/ int i, len; len = strlen(line); for(i = 0; i < len; i++){ if(isupper(line[i])){buf[i] = line[i] + 32;} else{buf[i] = line[i];} } buf[len] = '\0'; } /*-----------------------*/ char * substr2(char *line, int offset, int len){/*스트링 자르기(스트링 포인터를 리턴한다.)*/ int i, str_len; char *res; str_len = (int)strlen(line); if(len < 1 || offset >= str_len){return NULL;} /*Memory Size*/ if((offset + len) > str_len){len = str_len - offset;} for(i = 0; i < offset; i++){ line++; } res = (char *)malloc(sizeof(char) * (len + 1)); strncpy(res, line, len); res[len] = '\0'; return res; } /*-----------------------*/ int str_index(char *line, char *kword, int offset){/*서브스트링의 위치를 리턴한다.*/ int pos; char *temp; if(offset >= (int)strlen(line)){ return -1; } temp = substr2(line, offset, strlen(line) - offset); pos = strstr(temp, kword) - temp + offset; free(temp); if(pos < 0){return -1;} return pos; } /*-----------------------*/ int find_char(char *line, char delim, int offset){/*문자의 위치를 리턴한다.*/ int i, len; len = strlen(line); for(i = offset; i < len; i++){ if(line[i] == delim){return i;} } return -1; } /*-----------------------*/ void replace_by_string(char *line, char *pattern, char *replace, char buf[]){ int offset, stop, plen, len; char *temp; strcpy(buf, ""); if(line == NULL || (strcmp(line, "") == 0)){return;} len = strlen(line); plen = strlen(pattern); offset = 0; while(offset < len){ stop = str_index(line, pattern, offset); if(stop < 0){break;} temp = substr2(line, offset, stop - offset); if(temp){//if temp != null strcat(buf, temp); free(temp); } strcat(buf, replace); offset = stop + plen; } temp = substr2(line, offset, len - offset); if(temp){ strcat(buf, temp); free(temp); } } /*-----------------------*/ void replace_by_char(char *line, char pattern, char *replace, char buf[]){ int offset, stop, len; char *temp; strcpy(buf, ""); if(line == NULL || (strcmp(line, "") == 0)){return;} len = strlen(line); offset = 0; while(offset < len){ stop = find_char(line, pattern, offset); if(stop < 0){break;} temp = substr2(line, offset, stop - offset); if(temp){//if temp != null strcat(buf, temp); free(temp); } strcat(buf, replace); offset = stop + 1; } temp = substr2(line, offset, len - offset); if(temp){ strcat(buf, temp); free(temp); } } /*-----------------------*/ void replace(char *line, char *pattern, char *replace, char buf[]){ if(strlen(pattern) == 1){ replace_by_char(line, pattern[0], replace, buf); return; } replace_by_string(line, pattern, replace, buf); } /*-----------------------*/ void replace_by_string_i(char *line, char *pattern, char *replace, char buf[]){ int offset, stop, plen, len; char *temp, *line_lower, *pattern_lower; strcpy(buf, ""); if(line == NULL || (strcmp(line, "") == 0)){return;} len = strlen(line); plen = strlen(pattern); /*스트링 복사*/ line_lower = (char *)malloc(sizeof(char) * (len + 1)); pattern_lower = (char *)malloc(sizeof(char) * (plen + 1)); /*str_lower*/ str_lower(line, line_lower); str_lower(pattern, pattern_lower); offset = 0; while(offset < len){ /*str_index의 변수로 사본을 넘긴다.*/ stop = str_index(line_lower, pattern_lower, offset); if(stop < 0){break;} /*substr2의 변수로 원본을 넘긴다.*/ temp = substr2(line, offset, stop - offset); if(temp){//if temp != null strcat(buf, temp); free(temp); } strcat(buf, replace); offset = stop + plen; } temp = substr2(line, offset, len - offset); if(temp){ strcat(buf, temp); free(temp); } } /*-----------------------*/ void replace_by_char_i(char *line, char pattern, char *replace, char buf[]){ int offset, stop, len; char *temp, *line_lower, pattern_lower; strcpy(buf, ""); if(line == NULL || (strcmp(line, "") == 0)){return;} len = strlen(line); /*스트링 복사*/ line_lower = (char *)malloc(sizeof(char) * (len + 1)); pattern_lower = pattern; /*str_lower*/ str_lower(line, line_lower); if(isupper(pattern)){pattern_lower += 32;} offset = 0; while(offset < len){ /*find_char의 변수로 사본을 넘긴다.*/ stop = find_char(line_lower, pattern_lower, offset); if(stop < 0){break;} /*substr2의 변수로 원본을 넘긴다.*/ temp = substr2(line, offset, stop - offset); if(temp){//if temp != null strcat(buf, temp); free(temp); } strcat(buf, replace); offset = stop + 1; } temp = substr2(line, offset, len - offset); if(temp){ strcat(buf, temp); free(temp); } } /*-----------------------*/ void replace_i(char *line, char *pattern, char *replace, char buf[]){ if(strlen(pattern) == 1){ replace_by_char_i(line, pattern[0], replace, buf); return; } replace_by_string_i(line, pattern, replace, buf); } //------------------------ int main(){ char *line = "kkk:ooo:ppp"; char buf[1024]; int i = 0; clock_t start_time; start_time = clock(); for(i = 0; i < 10; i++){ replace(line, ":", "+", buf); puts(buf); } printf("Elapsed time: %2.2f\n", (double)(clock() - start_time) / CLOCKS_PER_SEC); return 0; }

/* simple sorting.

번호: 71 / 작성자: jinyedge / 등록일: 2003-04-09 02:09:03 / 조회: 198

I suddenly needed a simple sorting algorithm which I can remember easily. And I think this code is enough for the purpose. I don't know what kind of sorting algorithm is this. But I think I saw this algorithm in some book which I can't remember the title. */ #include <stdio.h> void main(){ int i, k, min_idx, temp; int arr[] = {24, 87, 34, 765, 55, 87, 3, 75, 44, 44, 1, 44, 99, 12, 575}; for(i = 0; i < 15; i++){ min_idx = i; for(k = i + 1; k < 15; k++){ if(arr[k] < arr[min_idx]){min_idx = k;} } temp = arr[i]; arr[i] = arr[min_idx]; arr[min_idx] = temp; } for(i = 0; i < 15; i++){ printf("%d\n", arr[i]); } }

도메인 - > 주소.

번호: 70 / 작성자: jinyedge / 등록일: 2003-01-08 12:46:35 / 조회: 328

#include <stdio.h> #include <netdb.h> #include <arpa/inet.h> //----------------- int main(int argc, char *argv[]){ hostent *he = NULL; he = gethostbyname("www.yahoo.com"); printf("%s\n", inet_ntoa(*((struct in_addr *)he->h_addr))); return 0; }

실행시간 측정.

번호: 67 / 작성자: jinyedge / 등록일: 2002-08-28 09:06:06 / 조회: 366

#include <time.h> int main(void){ int i; clock_t start_time; start_time = clock(); for(i = 0; i < 1000; i++){ printf("test...\n"); } printf("Elapsed time: %2.2f\n", (double)(clock() - start_time) / CLOCKS_PER_SEC); }

pthread - mutex

번호: 65 / 작성자: jinyedge / 등록일: 2002-06-21 07:58:26 / 조회: 254

/*컴파일 하려면 gcc -lpthread*/ #include <stdio.h> #include <pthread.h> /*-----------------*/ typedef struct _THR_ARG{ int *shr; pthread_mutex_t *lock; } THR_ARG; /*-----------------*/ void * my_thr(void *arg){ int i; THR_ARG *thr_arg = (THR_ARG *)arg; /*lock*/ pthread_mutex_lock(thr_arg->lock); *(thr_arg->shr) += 1; usleep(10); printf("%d\n", *(thr_arg->shr)); /*unlock*/ pthread_mutex_unlock(thr_arg->lock); return NULL; } /*-----------------*/ int main(void){ int i, shr; pthread_t thr[10]; pthread_mutex_t lock; THR_ARG thr_arg; shr = 0; /*init lock*/ pthread_mutex_init(&lock, NULL); thr_arg.shr = &shr; thr_arg.lock = &lock; /*create thread*/ for(i = 0; i < 10; i++){ if(pthread_create(&thr[i], NULL, my_thr, &thr_arg) != 0){puts("thread create..");} } /*wating for thread to end*/ for(i = 0; i < 10; i++){ if(pthread_join(thr[i], NULL) != 0){puts("thread join..");} } return 0; }

pthread - create, join

번호: 64 / 작성자: jinyedge / 등록일: 2002-06-21 06:26:39 / 조회: 213

/*컴파일 하려면 gcc -lpthread*/ #include <stdio.h> #include <pthread.h> /*-----------------*/ void * print_num(void *arg){ int i = 0; for(i = 0; i < 10; i++){ printf("1: %d\n", i); sleep(3); } return NULL; } /*-----------------*/ void * print_num2(void *arg){ int i = 0; for(i = 18; i < 28; i++){ printf("2: %d\n", i); sleep(1); } return NULL; } /*-----------------*/ int main(void){ pthread_t thr; pthread_t thr2; /*create thread*/ if(pthread_create(&thr, NULL, print_num, (void *)NULL) != 0){puts("thread create..");} if(pthread_create(&thr2, NULL, print_num2, (void *)NULL) != 0){puts("thread create..");} /*wating for thread to end*/ if(pthread_join(thr, NULL) != 0){puts("thread join..");} if(pthread_join(thr2, NULL) != 0){puts("thread join..");} return 0; }

get_open_file, get_save_file

번호: 62 / 작성자: jinyedge / 등록일: 2002-05-13 10:31:02 / 조회: 191

/*-----------------------*/ void get_open_file(HWND hWnd, const char *filter, char buf[]){ OPENFILENAME OFN; char path[MAX_PATH] = ""; memset(&OFN, 0, sizeof(OPENFILENAME)); OFN.lStructSize = sizeof(OPENFILENAME); OFN.hwndOwner = hWnd; OFN.lpstrFilter= filter; OFN.lpstrFile = path; OFN.nMaxFile = MAX_PATH; GetOpenFileName(&OFN); strcpy(buf, path); } /*-----------------------*/ void get_save_file(HWND hWnd, const char *filter, char buf[]){ OPENFILENAME OFN; char path[MAX_PATH] = ""; memset(&OFN, 0, sizeof(OPENFILENAME)); OFN.lStructSize = sizeof(OPENFILENAME); OFN.hwndOwner = hWnd; OFN.lpstrFilter= filter; OFN.lpstrFile = path; OFN.nMaxFile = MAX_PATH; GetSaveFileName(&OFN); strcpy(buf, path); }