title: python error in subprocess command
body: <p>I am trying to execute a subprocess, something done in my script a couple of times. But on the last one, it outputs an error I cannot find the solution to.
  The exact same command using the same files produced at the command line works just fine.</p>
  
  <h1>Line of code in question:</h1>
  
  <pre><code>sfmove = subprocess.call(["dnssec-signzone","-e",strftime("%Y%m%d%H", gmtime())+"0000","-p","-t","-g","-","K"+name+".ksk.key","-o",name,name+".external","K"+name+".zsk.key"])
  </code></pre>
  
  <h1>output of script</h1>
  
  <pre><code># python3.4 makekeys.py
  Enter the domain to configure keys for? test123.com
  Generating key pair....................................................................+++ ................................................................................+++
  K
  Generating key pair...........................................................+++ .................................................................................+++
  K
  dnssec-signzone: fatal: No self-signed KSK DNSKEY found.  Supply an active
  key with the KSK flag set, or use '-P'.
  </code></pre>
  
  <h1>signing works at command line:</h1>
  
  <pre><code>dnssec-signzone -e20180330000000 -p -t -g -k Ktest123.com.ksk.key -o test123.com test123.com.external Ktest123.com.zsk.key
  Verifying the zone using the following algorithms: RSASHA256.
  Zone fully signed:
  Algorithm: RSASHA256: KSKs: 1 active, 0 stand-by, 0 revoked
                        ZSKs: 1 active, 0 stand-by, 0 revoked
  test123.com.external.signed
  Signatures generated:                        9
  Signatures retained:                         0
  Signatures dropped:                          0
  Signatures successfully verified:            0
  Signatures unsuccessfully verified:          0
  Signing time in seconds:                 0.010
  Signatures per second:                 875.401
  Runtime in seconds:                      0.013
  </code></pre>
  
  <p>How do I execute the dnssec-signzone correctly via Python?</p>
  
  <p>url to complete code <a href="https://bpaste.net/show/79253980e374" rel="nofollow">CODE</a></p>