RULES¶

Rules take two forms - a filename extension by itself and functions with test values inside parenthesis. The following functions are available:

match("pattern")

True if the filename matches the given shell wildcard pattern.

ascii(offset,length)

True if the length bytes starting at offset are valid printable ASCII (CR, NL, TAB, BS, 32-126). length cannot exceed 8192 bytes.

printable(offset,length)

True if the length bytes starting at offset are printable 8-bit chars (CR, NL, TAB, BS, 32-126, 128-254). length cannot exceed 8192 bytes.

priority(number)

Specifies the relative priority of this MIME media type. The default priority is 100. Larger values have higher priority while smaller values have lower priority.

string(offset,"string")

True if the bytes starting at offset are identical to string.

istring(offset,"string")

True if the bytes starting at offset match string without respect to case.

char(offset,value)

True if the byte at offset is identical to value.

short(offset,value)

True if the 16-bit big-endian integer at offset is identical to value.

int(offset,value)

True if the 32-bit big-endian integer at offset is identical to value.

locale("string")

True if current locale matches string.

contains(offset,length,"string")

True if the bytes starting at offset for length bytes contains string. length cannot exceed 8192 bytes.

STRING CONSTANTS¶

String constants can be specified inside quotes ("") for strings containing whitespace and angle brackets (<>) for hexadecimal strings.

TYPE MATCHING AND PRIORITY¶

When CUPS needs to determine the MIME media type of a given file, it checks every MIME media type defined in the .types files. When two or more types match a given file, the type chosen will depend on the type name and priority, with higher-priority types being used over lower-priority ones. If the types have the same priority, the type names are sorted alphanumerically in ascending order and the first type is chosen.

For example, if two types "text/bar" and "text/foo" are defined as matching the extension "doc", normally the type "text/bar" will be chosen since its name is alphanumerically smaller than "text/foo". However, if "text/foo" also defines a higher priority than "text/bar", "text/foo" will be chosen instead.