Manpages - zip_file_extra_field_get_by_id.3

libzip (-lzip)

The

function returns the extra field with index

for the file at position

in the zip archive. This pointer should not be modified or

and becomes invalid when

is closed. If

is not

the integer to which it points will be set to the ID (two-byte signature) of the selected extra field. If

is not

the integer to which it points will be set to the length of the extra field. Generally speaking,

and

should be passed since only the extra field data is returned (i.e., neither the ID nor the length, if the

and

arguments are not provided).

The following

are supported:

Return extra fields from the archive’s central directory.

Return extra fields from the local file headers.

Return the original unchanged extra fields, ignoring any changes made.

The

function returns the extra field with ID (two-byte signature)

and index

(in other words, the

extra field with ID

The other arguments are the same as for

Upon successful completion, a pointer to an extra field is returned, or

if there is no extra field with that

for the file with index

In case of an error,

is returned and the error code in

is set to indicate the error.

and

fail if:

is not a valid file index in

is not a valid extra file index (for ID

and

were added in libzip 0.11.

and

Please note that the extra field IDs 0x0001 (ZIP64 extension), 0x6375 (Infozip UTF-8 comment), and 0x7075 (Infozip UTF-8 file name) can not be read using

since they are used by

internally.