SEGYHDRS - make SEG-Y ascii and binary headers for segywrite      

 segyhdrs [ < sudata ] [optional parameters] [ > copy of sudata ]     

 Required parameters:                                      
      ns=  if no input trace header                        
      dt=  if no input trace header                        
 Optional parameters:                                      
      ns=tr.ns from header    number of samples on input traces  
      dt=tr.dt from header    sample rate (microseconds) from traces   
      bfile=binary            name of file containing binary block     
      hfile=header            name of file containing ascii block
   Some binary header fields are set:                            
      jobid=1                 job id field                       
      lino=1                  line number (only one line per reel)     
      reno=1                  reel number                  
      format=1          data format                  

 All other fields are set to 0, by default.                      
 To set any binary header field, use sukeyword to find out       
 the appropriate keyword, then use the getpar form:              
      keyword=value     to set keyword to value                  

 The header file is created as ascii and is translated to ebcdic 
 by segywrite before being written to tape.  Its contents are          
 formal but can be edited after creation as long as the forty          
 line format is maintained.                                

 Caveat: This program has not been tested under XDR for machines      
       not having a 2 byte unsigned short integral data type.    


 Credits:

      CWP: Jack K. Cohen,  John Stockwell
      MOBIL: Stew Levin