lozier:~$ xml2-config
Usage: xml2-config [OPTION]

Known values for OPTION are:

  --prefix=DIR          change libxml prefix
  --exec-prefix=DIR     change libxml exec prefix
  --libs                print library linking information
  --cflags              print pre-processor and compiler flags
  --modules             module support enabled
  --help                display this help and exit
  --version             output version information
lozier:~$ xml2-config --version
2.6.23
lozier:~$