easily trace all Nginx processes

sudo strace -e trace=network -p `pidof nginx | sed -e 's/ /,/g'`
Nginx (and other webservers like Apache) can be awkward to trace. They run as root, then switch to another user once they're ready to serve web pages. They also have a "master" process and multiple worker processes. The given command finds the process IDs of all Nginx processes, joins them together with a comma, then traces all of them at once with "sudo strace." System trace output can be overwhelming, so we only capture "networking" output. TIP: to kill this complex strace, do "sudo killall strace". Compare with a similar command: http://www.commandlinefu.com/commands/view/11918/easily-strace-all-your-apache-processes
Sample Output
# grab an Nginx web page:
#     curl -so /dev/null localhost

[pid  1145] accept4(6, {sa_family=AF_INET, sin_port=htons(57358), sin_addr=inet_addr("")}, [16], SOCK_NONBLOCK) = 10
[pid  1145] recvfrom(10, "GET / HTTP/1.1\r\nUser-Agent: curl"..., 1024, 0, NULL, NULL) = 73
[pid  1145] setsockopt(10, SOL_TCP, TCP_CORK, [1], 4) = 0
[pid  1145] sendfile(10, 11, [0], 612)  = 612
[pid  1145] setsockopt(10, SOL_TCP, TCP_CORK, [0], 4) = 0
[pid  1145] recvfrom(10, 0xa7e1c0, 1024, 0, 0, 0) = -1 EAGAIN (Resource temporarily unavailable)
[pid  1145] recvfrom(10, "", 1024, 0, NULL, NULL) = 0

2016-01-28 18:48:16

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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