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Programming
Any one can tell me how this happen?
Post 36438 by jiangyanna on Thursday 29th of May 2003 01:35:51 AM
05-29-2003
thanks
Thanks!
And now i change my program like this:
Main(void)
{
int I;
printf(Ħ°%d,%d,%d \nĦħ,getpid(),getppid(),getpgid(0));
for(I=0;I<2;I++)
if (fork()==0)
printf(Ħ°%d\t%d,%d,%d \nĦħ,I,getpid(),getppid(),getpgid(0));
}
Result on screen:
59066,56414,59066 //parent print this
0 43282,59066,59066 //this is the first child process
1 27854,43282,59066 //first child process's child
1 5422,59066,59066 //second child process
Result on out.txt:
43306,56414,43306
43306,56414,43306
1 64390,1,43306
43306,56414,43306
0 58632,43306,43306
43306,56414,43306
0 58632,43306,43306
1 39766,1,43306
but how the race condition happen?I guess there is something going on in it's cache....
but i know when fork() produce a child process it will copy it's cache to the child's.
but does any body know the process of doing all these things(i mean from the child's birth to the death)
or anyone can give me some reference?
And now i change my program like this:
Main(void)
{
int I;
printf(Ħ°%d,%d,%d \nĦħ,getpid(),getppid(),getpgid(0));
for(I=0;I<2;I++)
if (fork()==0)
printf(Ħ°%d\t%d,%d,%d \nĦħ,I,getpid(),getppid(),getpgid(0));
}
Result on screen:
59066,56414,59066 //parent print this
0 43282,59066,59066 //this is the first child process
1 27854,43282,59066 //first child process's child
1 5422,59066,59066 //second child process
Result on out.txt:
43306,56414,43306
43306,56414,43306
1 64390,1,43306
43306,56414,43306
0 58632,43306,43306
43306,56414,43306
0 58632,43306,43306
1 39766,1,43306
but how the race condition happen?I guess there is something going on in it's cache....
but i know when fork() produce a child process it will copy it's cache to the child's.
but does any body know the process of doing all these things(i mean from the child's birth to the death)
or anyone can give me some reference?
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LEARN ABOUT HPUX
ftpgroups
ftpgroups(4) Kernel Interfaces Manual ftpgroups(4) NAME
ftpgroups - group password file for use with the SITE GROUP and SITE GPASS commands. SYNOPSIS
DESCRIPTION
The file is the group password file for use with the SITE GROUP and SITE GPASS commands. To enable the use of this file, the entry must be made in the configuration file This file contains an alphanumeric string, encrypted password, and the actual group name from the file. Each entry is separated by After a user logs in, the SITE GROUP and SITE GPASS commands may be used to specify an enhanced access group and associated password. If the group name and password are valid, the user becomes (via a member of the group specified in the group access file, The format of the group access file is: where access_group_name is an arbitrary (alphanumeric and/or punctuation) string. encrypted_password is the password encrypted via crypt(3), exactly like in real_group_name is the name of a valid group listed in NOTE: For this option to work for anonymous FTP users, the ftp server must keep permanently open and the group access file is loaded into memory. This means that: (1) the ftp server now has an additional file descriptor open, and (2) the necessary passwords and access privileges granted to users via SITE GROUP will be static for the duration of an FTP ses- sion. If you have an urgent need to change the access groups and/or passwords *NOW*, then kill all of the running FTP servers. FILES
AUTHOR
was developed by the Washington University, St. Louis, Missouri. SEE ALSO
ftpaccess(4). ftpgroups(4)