wgrib2: -if_fs, -not_if_fs
The -if_fs option is the same as the
the -if option except it takes "fixed strings"
rather than extended regular expressions. The
-not_if_fs is the same as the -not_if option
except it takes "fixed strings".
The "fixed string" options have the advantage that matches do not use the
regex wildcards. For example, "-if 3.0" will match "300" because the period is
a wildcard character that matches any character including a zero.
X is a fixed string (not a regular expression)
See also: -if,
See also: -not_if,
See also: -not_if_fs,