fix command line building bug

.idea/workspace.xml

@@ -4,9 +4,6 @@
     <list default="true" id="fc2840de-29dc-4fca-8e0e-a283562f60ca" name="Default Changelist" comment="">
       <change beforePath="$PROJECT_DIR$/.idea/workspace.xml" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/workspace.xml" afterDir="false" />
       <change beforePath="$PROJECT_DIR$/client.go" beforeDir="false" afterPath="$PROJECT_DIR$/client.go" afterDir="false" />
-      <change beforePath="$PROJECT_DIR$/cmd/main.go" beforeDir="false" afterPath="$PROJECT_DIR$/cmd/main.go" afterDir="false" />
-      <change beforePath="$PROJECT_DIR$/server.go" beforeDir="false" afterPath="$PROJECT_DIR$/server.go" afterDir="false" />
-      <change beforePath="$PROJECT_DIR$/shared.go" beforeDir="false" afterPath="$PROJECT_DIR$/shared.go" afterDir="false" />
     </list>
     <option name="SHOW_DIALOG" value="false" />
     <option name="HIGHLIGHT_CONFLICTS" value="true" />
@@ -55,15 +52,6 @@
     </key>
   </component>
   <component name="RunManager" selected="Go Build.go build github.com/BGrewell/go-iperf/tests/client">
-    <configuration default="true" type="GoApplicationRunConfiguration" factoryName="Go Application">
-      <module name="go-iperf" />
-      <working_directory value="$PROJECT_DIR$" />
-      <go_parameters value="-i" />
-      <kind value="FILE" />
-      <filePath value="$PROJECT_DIR$" />
-      <directory value="$PROJECT_DIR$" />
-      <method v="2" />
-    </configuration>
     <configuration name="go build github.com/BGrewell/go-iperf/cmd" type="GoApplicationRunConfiguration" factoryName="Go Application" temporary="true" nameIsGenerated="true">
       <module name="go-iperf" />
       <working_directory value="$PROJECT_DIR$" />
@@ -91,16 +79,6 @@
       <directory value="$PROJECT_DIR$" />
       <method v="2" />
     </configuration>
-    <configuration default="true" type="GoTestRunConfiguration" factoryName="Go Test">
-      <module name="go-iperf" />
-      <working_directory value="$PROJECT_DIR$" />
-      <go_parameters value="-i" />
-      <framework value="gotest" />
-      <kind value="DIRECTORY" />
-      <directory value="$PROJECT_DIR$" />
-      <filePath value="$PROJECT_DIR$" />
-      <method v="2" />
-    </configuration>
     <recent_temporary>
       <list>
         <item itemvalue="Go Build.go build github.com/BGrewell/go-iperf/tests/client" />

client.go

@@ -96,7 +96,7 @@ func (c *Client) commandString() (cmd string, err error) {
 		fmt.Fprintf(&builder, " -p %d", c.Port())
 	}
 
-	if c.options.Format != nil || *c.options.Format != ' ' {
+	if c.options.Format != nil && *c.options.Format != ' ' {
 		fmt.Fprintf(&builder, " -f %c", c.Format())
 	}