Invoking Webservice from command line . Here SOAP request is to be specified in a file named request.xml

request.xml

<soapenv:Envelope
         xmlns:q0="https://.../"
         xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/"
         xmlns:xsd="http://www.w3.org/2001/XMLSchema"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
         <soapenv:Header>
         </soapenv:Header>
         <soapenv:Body>
                 <q0:clientLogin>
                        <q0:username>...</q0:username>
                        <q0:password>...</q0:password>
                 </q0:clientLogin>
         </soapenv:Body>
</soapenv:Envelope>

Webservice.sh

curl -X POST -H "Content-Type: text/xml;charset=UTF-8" -H "SOAPAction: \"https://.../clientLogin\"" -d @request.xml https://.../service.asmx