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璇ュ嚱鏁板彲浠ユ敼鍙樺凡鎵撳紑鐨勬枃浠剁殑鎬ц川銆?br>
#include <fcntl.h>
int fcntl(int fields, int cmd, 
/**//* int arg */); //鑻ユ垚鍔熷垯渚濊禆浜巆md,鑻ュ嚭閿欏垯榪斿洖-1
絎笁涓弬鏁版繪槸涓涓暣鏁幫紝涓庝笂闈㈡墍紺哄嚱鏁板師鍨嬩腑鐨勬敞閲婇儴鍒嗙浉瀵瑰簲銆備絾鏄湪浣滀負璁板綍閿佺敤鏃訛紝絎笁涓弬鏁板垯鏄寚鍚戜竴涓粨鏋勭殑鎸囬拡銆?br> fcntl鍑芥暟鏈?縐嶅姛鑳斤細
1.澶嶅埗涓涓幇鏈夌殑鎻忚堪絎︼紙cmd = F_DUPFD錛?
2.鑾峰緱錛忚緗枃浠舵弿榪扮鏍囪(cmd = F_GETFD || F_SETFD).
3.鑾峰緱錛忚緗枃浠剁姸鎬佹爣璁?cmd = F_GETFL || F_SETFL).
4.鑾峰緱錛忚緗紓姝/O鎵鏈夋潈(cmd = F_GETOWN || F_SETOWN).
5.鑾峰緱錛忚緗褰曢攣(cmd = F_GETLK, F_SETLK || F_SETLKW).
#include <fcntl.h>2
#include <unistd.h>3
#include <iostream>4
#include <errno.h>5
using namespace std;6
7
int main(int argc, char* argv[])8
{9
int fd, var;10
//fd = open("new",O_RDWR);11
12
if (argc != 2)13
{14
perror("--");15
cout << "璇瘋緭鍏ュ弬鏁幫紝鍗蟲枃浠跺悕錛?/span>" << endl;16
}17
18
if ((var = fcntl(atoi(argv[1]), F_GETFL, 0)) < 0)19
{20
strerror(errno);21
cout << "fcntl file error." << endl;22
}23
24
switch (var & O_ACCMODE)25
{26
case O_RDONLY : 27
cout<<"Read only.."<<endl;28
break;29
30
case O_WRONLY : 31
cout<<"Write only.."<<endl;32
break;33
34
case O_RDWR : 35
cout<<"Read wirte.."<<endl;36
break;37
38
default : 39
break;40
}41
42
if (val & O_APPEND)43
cout << ",append" << endl;44
45
if (val & O_NONBLOCK)46
cout << ",noblocking" << endl;47
48
cout << "exit 0" << endl;49
50
exit(0);51
}52
53
fcntl鏂囦歡閿佹湁涓ょ綾誨瀷錛氬緩璁ч攣鍜屽己鍒舵ч攣
寤鴻鎬ч攣鏄繖鏍瘋瀹氱殑錛氭瘡涓嬌鐢ㄤ笂閿佹枃浠剁殑榪涚▼閮借媯鏌ユ槸鍚︽湁閿佸瓨鍦紝褰撶劧榪樺緱灝婇噸宸叉湁鐨勯攣銆傚唴鏍稿拰緋葷粺鎬諱綋涓婇兘鍧氭寔涓嶄嬌鐢ㄥ緩璁ч攣錛屽畠浠緷闈犵▼搴忓憳閬靛畧榪欎釜瑙勫畾銆?br> 寮哄埗鎬ч攣鏄敱鍐呮牳鎵ц鐨勩傚綋鏂囦歡琚笂閿佹潵榪涜鍐欏叆鎿嶄綔鏃訛紝鍦ㄩ攣瀹氳鏂囦歡鐨勮繘紼嬮噴鏀捐閿佷箣鍓嶏紝鍐呮牳浼氶樆姝換浣曞璇ユ枃浠剁殑璇繪垨鍐欒闂紝姣忔璇繪垨鍐欒闂兘寰楁鏌ラ攣鏄惁瀛樺湪銆?/p>
緋葷粺榛樿fcntl閮芥槸寤鴻鎬ч攣錛屽己鍒舵ч攣鏄潪POSIX鏍囧噯鐨勩傚鏋滆浣跨敤寮哄埗鎬ч攣錛岃浣挎暣涓郴緇熷彲浠ヤ嬌鐢ㄥ己鍒舵ч攣錛岄偅涔堝緱闇瑕侀噸鏂版寕杞芥枃浠剁郴緇燂紝 mount浣跨敤鍙傛暟 -0 mand鎵撳紑寮哄埗鎬ч攣錛屾垨鑰呭叧闂凡鍔犻攣鏂囦歡鐨勭粍鎵ц鏉冮檺騫朵笖鎵撳紑璇ユ枃浠剁殑set-GID鏉冮檺浣嶃?br> 寤鴻鎬ч攣鍙湪cooperating processes涔嬮棿鎵嶆湁鐢紝瀵筩ooperating process鐨勭悊瑙ｆ槸鏈閲嶈鐨勶紝瀹冩寚鐨勬槸浼氬獎鍝嶅叾瀹冭繘紼嬬殑榪涚▼鎴栬鍒殑榪涚▼鎵褰卞搷鐨勮繘紼嬶紝涓句袱涓緥瀛愶細
錛?錛夋垜浠彲浠ュ悓鏃跺湪涓や釜紿楀彛涓繍琛屽悓涓涓懡浠わ紝瀵瑰悓涓涓枃浠惰繘琛屾搷浣滐紝閭ｄ箞榪欎袱涓繘紼嬪氨鏄痗ooperating processes錛?br> 錛?錛?cat file | sort錛?閭ｄ箞cat鍜宻ort浜х敓鐨勮繘紼嬪氨鏄嬌鐢ㄤ簡pipe鐨刢ooperating processes銆?/p>
浣跨敤fcntl鏂囦歡閿佽繘琛孖/O鎿嶄綔蹇呴』灝忓績錛氳繘紼嬪湪寮濮嬩換浣旾/O鎿嶄綔鍓嶅浣曞幓澶勭悊閿侊紝鍦ㄥ鏂囦歡瑙ｉ攣鍓嶅浣曞畬鎴愭墍鏈夌殑鎿嶄綔錛屾槸蹇呴』鑰冭檻鐨勩傚鏋滃湪璁劇疆閿佷箣鍓嶆墦寮鏂囦歡錛屾垨鑰呰鍙栬閿佷箣鍚庡叧闂枃浠訛紝鍙︿竴涓繘紼嬪氨鍙兘鍦ㄤ笂閿?瑙ｉ攣鎿嶄綔鍜屾墦寮/鍏抽棴鎿嶄綔涔嬮棿鐨勫嚑鍒嗕箣涓縐掑唴璁塊棶璇ユ枃浠躲傚綋涓涓繘紼嬪鏂囦歡鍔犻攣鍚庯紝鏃犺瀹冩槸鍚﹂噴鏀炬墍鍔犵殑閿侊紝鍙鏂囦歡鍏抽棴錛屽唴鏍擱兘浼氳嚜鍔ㄩ噴鏀懼姞鍦ㄦ枃浠朵笂鐨勫緩璁ч攣錛堣繖涔熸槸寤鴻鎬ч攣鍜屽己鍒舵ч攣鐨勬渶澶у尯鍒級, 鎵浠ヤ笉瑕佹兂璁劇疆寤鴻鎬ч攣鏉ヨ揪鍒版案涔呬笉璁╁埆鐨勮繘紼嬭闂枃浠剁殑鐩殑(寮哄埗鎬ч攣鎵嶅彲浠?錛涘己鍒舵ч攣鍒欏鎵鏈夎繘紼嬭搗浣滅敤銆?/p>
fcntl浣跨敤涓変釜鍙傛暟 F_SETLK/F_SETLKW錛?F_UNLCK鍜孎_GETLK, 鏉ュ垎鍒姹傘侀噴鏀俱佹祴璇時ecord locks銆?record locks鏄鏂囦歡涓閮ㄥ垎鑰屼笉鏄暣涓枃浠剁殑閿侊紝榪欑緇嗚嚧鐨勬帶鍒朵嬌寰楄繘紼嬫洿濂藉湴鍗忎綔浠ュ叡浜枃浠惰祫婧愩俧cntl鑳藉鐢ㄤ簬璇誨彇閿佸拰鍐欏叆閿侊紝read lock涔熷彨shared lock錛堝叡浜攣錛? 鍥犱負澶氫釜cooperating process鑳藉鍦ㄦ枃浠剁殑鍚屼竴閮ㄥ垎寤虹珛璇誨彇閿侊紱write lock琚О涓篹xclusive lock(鎺掓枼閿?錛?鍥犱負浠諱綍鏃跺埢鍙兘鏈変竴涓猚ooperating process鍦ㄦ枃浠剁殑鏌愰儴鍒嗕笂寤虹珛鍐欏叆閿併傚鏋渃ooperating processes瀵規枃浠惰繘琛屾搷浣滐紝閭ｄ箞瀹冧滑鍙互鍚屾椂瀵規枃浠跺姞read lock錛屽湪涓涓猚ooperating process鍔爓rite lock涔嬪墠錛屽繀欏婚噴鏀懼埆鐨刢ooperating process鍔犲湪璇ユ枃浠剁殑read lock鍜寃rtie lock錛屼篃灝辨槸璇達紝瀵逛簬鏂囦歡鍙兘鏈変竴涓獁rite lock瀛樺湪錛宺ead lock鍜寃rtie lock涓嶈兘鍏卞瓨銆?
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