Command run:

  bufralter.pl 1xBUFRSYNOP-ed4.bufr \
  --data 004004=-1+ --data 004005=50 --data 012101=missing \
  --update_number 1 --bufr_edition 3  --centre 88 \
  --master_table_version 11 --local_table_version 0 \
  --outfile altered.bufr
 
[[bufralter_before|Decoded content]] before running bufralter.pl (decoded by running bufrread.pl on 1xBUFRSYNOP-ed4.bufr)

[[bufralter_after|Decoded content]] after running bufralter.pl (decoded by running bufrread.pl on altered.bufr)