linux systemº¯ÊýʹÓÃÏê½â
Ïà¹Øº¯Êý
fork£¬execve£¬waitpid£¬popen
±íÍ·Îļþ
££i nclude<stdlib.h>
¶¨Ò庯Êý
int system(const char * string);
º¯Êý˵Ã÷
system()»áµ÷ÓÃfork()²úÉú×Ó½ø³Ì£¬ÓÉ×Ó½ø³ÌÀ´µ÷ÓÃ/bin/sh-c stringÀ´Ö´ÐвÎÊýstring×Ö·û´®Ëù´ú±íµÄÃüÁ´ËÃü>ÁîÖ´ÐÐÍêºóËæ¼´·µ»ØÔµ÷ÓõĽø³Ì¡£ÔÚµ÷ÓÃsystem()ÆÚ¼äSIGCHLD ÐźŻᱻÔÝʱ¸éÖã¬SIGINTºÍSIGQUIT ÐźÅÔò»á±»ºöÂÔ¡£
·µ»ØÖµ
=-1:³öÏÖ´íÎó
=0:µ÷Óóɹ¦µ«ÊÇûÓгöÏÖ×Ó½ø³Ì
>0:³É¹¦Í˳öµÄ×Ó½ø³ÌµÄid
Èç¹ûsystem()ÔÚµ÷ÓÃ/bin/shʱʧ°ÜÔò·µ»Ø127£¬ÆäËûʧ°ÜÔÒò·µ»Ø-1¡£Èô²ÎÊýstringΪ¿ÕÖ¸Õë(NULL)£¬Ôò·µ»Ø·ÇÁãÖµ>¡£ Èç¹ûsystem()µ÷Óóɹ¦Ôò×îºó»á·µ»ØÖ´ÐÐshellÃüÁîºóµÄ·µ»ØÖµ£¬µ«ÊÇ´Ë·µ»ØÖµÒ²ÓпÉÄÜΪ system()µ÷ÓÃ/bin/shʧ°ÜËù·µ»ØµÄ127£¬Òò´Ë×îºÃÄÜÔÙ¼ì²éerrno À´È·ÈÏÖ´Ðгɹ¦¡£
¸½¼Ó˵Ã÷
ÔÚ±àд¾ßÓÐSUID/SGIDȨÏ޵ijÌÐòʱÇëÎðʹÓÃsystem()£¬system()»á¼Ì³Ð»·¾³±äÁ¿£¬Í¨¹ý»·¾³±äÁ¿¿ÉÄÜ»áÔì³Éϵͳ°²È«µÄÎÊÌâ¡£
·¶Àý
££i nclude<stdlib.h>
main()
{
system(“ls -al /etc/passwd /etc/shadow”);
}
Ö´Ðнá¹û£º
-rw-r--r-- 1 root root 705 Sep 3 13 :52 /etc/passwd
-r--------- 1 root root 572 Sep 2 15 :34 /etc/shado
Àý2£º
char tmp[];
sprintf(tmp,"/bin/mount -t vfat %s /mnt/usb",dev);
system(tmp);
ÆäÖÐdevÊÇ/dev/sda1¡£
systemÔ´Âë
#include
#include
#include
#include
int system(const char * cmdstring)
{
pid_t pid;
int status;
if(cmdstring == NULL){
return (1);
}
if((pid = fork())<0){
status = -1;
}
else if(pid == 0){
execl("/bin/sh", "sh", "-c", cmdstring, (char *)0);
-exit(127); //×Ó½ø³ÌÕý³£Ö´ÐÐÔò²»»áÖ´ÐдËÓï¾ä
}
else{
while(waitpid(pid, &status, 0) < 0){
&nbs
Ïà¹ØÎĵµ£º
Service Discovery Protocol(SDP)ÌṩһÖÖÄÜÁ¦£¬ÈÃÓ¦ÓóÌÐòÓз½·¨·¢ÏÖÄÄÖÖ·þÎñ¿ÉÓÃÒÔ¼°ÕâÖÖ·þÎñµÄÌØÐÔ¡£
·þÎñ·¢ÏÖÐÒé(SDP»òBluetooth SDP)ÔÚÀ¶ÑÀÐÒéÕ»ÖжÔÀ¶ÑÀ»·¾³ÖеÄÓ¦ÓóÌÐòÓÐÌØÊâµÄº¬Ò⣬·¢ÏÖÄĸö·þÎñÊÇ¿ÉÓõĺÍÈ·¶¨ÕâЩ¿ÉÓ÷þÎñµÄÌØÕ÷¡£SDP¶¨ÒåÁËbluetooth client·¢ÏÖ¿ÉÓÃbluetooth server·þÎñºÍËüÃǵÄÌØÕ÷µÄ·½·¨¡£ ......
ÎÒÃÇÖªµÀĬÈÏÍâÉèI/O×ÊÔ´ÊDz»ÔÚLinuxÄں˿ռäÖеģ¨Èçsram»òÓ²¼þ½Ó¿Ú¼Ä´æÆ÷µÈ£©£¬ÈôÐèÒª·ÃÎʸÃÍâÉèI/O×ÊÔ´£¬±ØÐëÏȽ«ÆäµØÖ·Ó³Éäµ½Äں˿ռäÖÐÀ´£¬È»ºó²ÅÄÜÔÚÄں˿ռäÖзÃÎÊËü¡£
LinuxÄں˷ÃÎÊÍâÉèI/OÄÚ´æ×ÊÔ´µÄ·½Ê½ÓÐÁ½ÖÖ£º¶¯Ì¬Ó³Éä(ioremap)ºÍ¾²Ì¬Ó³Éä(map_desc)¡£
Ò»¡¢¶¯Ì¬Ó³Éä(ioremap)·½Ê½
¶ ......
Qt ÊÇÒ»¸ö¿çƽ̨µÄ C++ ͼÐÎÓû§½çÃæ¿â£¬ÓÉŲÍþ TrollTech ¹«Ë¾³öÆ·£¬Ä¿Ç°°üÀ¨Qt£¬
»ùÓÚ Framebuffer µÄ Qt Embedded£¬¿ìËÙ¿ª·¢¹¤¾ß Qt Designer£¬¹ú¼Ê»¯¹¤¾ß Qt Linguist µÈ²¿·Ö
Qt Ö§³ÖËùÓÐ Unix ϵͳ£¬µ±È»Ò²°üÀ¨ Linux£¬»¹Ö§³Ö WinNT/Win2k£¬Win95/98 ƽ̨¡£
Trolltech ¹«Ë¾ÔÚ 1994 Äê³ÉÁ¢£¬µ«ÊÇÔÚ 19 ......
×î½ü£¬¿ªÊ¼ÑжÁÒ»ÏÂLinuxµÄÄں˴úÂ룬¸ÕÒ»¿ªÊ¼£¬¾ÍÓÐÁîÈ˾ªÌ¾µÄ·¢ÏÖ£¬²»µÃ²»¸Ð̾Äں˴úÂëÉè¼ÆµÃÖ®ÃÀ£¡µ¥ÊÇ×î³£ÓõÄÁ´±íÒ²Éè¼ÆµÃ²»µÃ²»ÁîÈËÅå·þ£¡
1.1.Á´±ílist_head
include/linux/list.h
ºÜ¾µä£¬Á´±íÔÚÄÚºËÖкܳ£Óã¬ÀýÈç¹ÜÀí½ø³Ì£¬½ø³ÌµÄ¸÷¸ö״̬¶ÓÁж¼ÊÇʹÓÃÕâ¸öË«ÏòÁ ......
Èí¼þ»·¾³
debian 5.0
Apache Httpd 2.0.63 (http://httpd.apache.org
)
OpenSSL 0.9.81 (http://www.openssl.org/source
)
SSL-Tools (http://www.openssl.org/contrib/ssl.ca-0.1.tar.gz
)
°²×°²½Öè(ËùÓвÙ×÷ʹÓÃrootÓû§½øÐÐ)£º
1. OpenSSL
#tar zxvf openssl-0.9.81.tar.gz
#cd openssl-0.9.81
#./config
# ......