Debug (查看某 Process 在做什麼)

Java:

# print a thread dump in stdout

kill -3 PID

PHP:

# compile PHP yourself using --enable-debug

gdb -p $PHP_PID       # php cgi PID

strace -p 10472         # Apache PID

poll([{fd=4, events=POLLIN|POLLPRI|POLLERR|POLLHUP}], 1, 0) = 0 (Timeout)
poll([{fd=4, events=POLLIN|POLLERR|POLLHUP}], 1, 60000) = 0 (Timeout)

Other

• strace