<html> <head> <meta http-equiv="Content-Type" content="text/html; charset=us-ascii"> <meta name="Generator" content="Microsoft Exchange Server">  <style></style> </head> <body> <font face="Calibri, sans-serif" size="2"> <div><font color="#1F497D">Sorry , add the Title<font face="Wingdings" size="2">L</font></font></div> <div><font face="Times New Roman, serif" color="#1F497D"> </font></div> <div><font face="Tahoma, sans-serif" size="2">_____________________________________________<br> <b>From:</b> Zhang, Qiang Z <br> <b>Sent:</b> Thursday, December 16, 2010 11:01 AM<br> <b>To:</b> 'hughsient@gmail.com'<br> <b>Cc:</b> 'packagekit@lists.freedesktop.org'<br> <b>Subject:</b> </font></div> <div><font face="Times New Roman, serif"> </font></div> <div><font face="Times New Roman, serif"> </font></div> <div><font face="Calibri, sans-serif">Hi Richard,</font></div> <div><font face="Calibri, sans-serif"> </font></div> <div><font face="Calibri, sans-serif">I want to implemented the cancel API for zypp backend. But have not found the proper way.</font></div> <div><font face="Calibri, sans-serif"> </font></div> <div><font face="Calibri, sans-serif">I have reviewed the cancel method of other backends, and found it’s easy to call pk_backend_spawn_kill (spawn) if backend use PkBackendSpawn.</font></div> <div><font face="Calibri, sans-serif"> </font></div> <div><font face="Calibri, sans-serif">But for the backend,  which don’t use PkBackendSpawn,  it’s complicated to implemented this transaction cancel method. Such as poldek, which call poldek’s sigint_emit () to cancel transaction and sigint_emit is implemented in poldek but not PackageKit.</font></div> <div><font face="Calibri, sans-serif"> </font></div> <div><font face="Calibri, sans-serif">Most of the other backends just set the transaction status and do nothing.</font></div> <div><font face="Calibri, sans-serif"> </font></div> <div><font face="Calibri, sans-serif">I think, can PackageKit provide a function pk_backend_thread_cancel in pk-backend.c to send signal to the backend thread, the signal handler in thread can release some resources then call g_thread_exit to exit.</font></div> <div><font face="Calibri, sans-serif">Then all the backend use thread can call pk_backend_thread_cancel to cancel transaction.</font></div> <div><font face="Calibri, sans-serif"> </font></div> <div><font face="Calibri, sans-serif">Or any other method?</font></div> <div><font face="Calibri, sans-serif"> </font></div> <div><font face="Calibri, sans-serif"> </font></div> <div><font face="Calibri, sans-serif">-Thanks</font></div> <div><font face="Calibri, sans-serif">-Xiaoqiang</font></div> <div><font face="Times New Roman, serif"> </font></div> <div><font face="Times New Roman, serif"> </font></div> </font> </body> </html>