FCrypt Usage

When no command line inputs are received by the application, it can be useful to show the required inputs on screen in a help context.

void usage(void){ printf( "usage fcrypt -d [-s<sender>] [-r<recipient>]
[-o<output file>] <input file>\n" );printf( " or\n" );printf( "usage fcrypt -d [-p<password>] [-o<outputfile>] 
<input file>\n" );printf( " -d decrypt\n" );printf( " -p PBE password\n" );printf( " -s Sender name\n" );printf( " -r Recipient name\n" );printf( " -o output file name\n" );printf( " -t Report timing info\n" );printf( "\nKey naming syntax :\n");printf( " <token name>(<user pin>)/<key name>\n" );printf( " for example, -sAlice(0000)/Sign\n" 
);} 

Next, see Wrapped Encryption Key Template.