ZIP_FILE_EXTRA_FIELD_DELETE(3) | Library Functions Manual | ZIP_FILE_EXTRA_FIELD_DELETE(3)

# NAME

`zip_file_extra_field_delete`, `zip_file_extra_field_delete_by_id` —
delete extra field for file in zip

# LIBRARY

libzip (-lzip)

# SYNOPSIS

`#include <zip.h>`

int
`zip_file_extra_field_delete`(zip_t *archive, zip_uint64_t index, zip_uint16_t extra_field_index, zip_flags_t flags);

int
`zip_file_extra_field_delete_by_id`(zip_t *archive, zip_uint64_t index, zip_uint16_t extra_field_id, zip_uint16_t extra_field_index, zip_flags_t flags);

# DESCRIPTION

The `zip_file_extra_field_delete`() function deletes the extra field with index extra_field_index for the file at position index in the zip archive.

If extra_field_index is `ZIP_EXTRA_FIELD_ALL`, then all extra fields will be deleted.

The following flags are supported:

`ZIP_FL_CENTRAL`
  Delete extra fields from the archive's central directory.
`ZIP_FL_LOCAL`
  Delete extra fields from the local file headers.

The `zip_file_extra_field_delete_by_id`() function deletes the extra field with ID (two-byte signature) extra_field_id and index extra_field_index (in other words, the extra_field_index'th extra field with ID extra_field_id) The other arguments are the same as for `zip_file_extra_field_delete`() (`ZIP_EXTRA_FIELD_ALL` will delete all extra fields of the specified ID).

Please note that due to the library design, the index of an extra field may be different between central directory and local file headers. For this reason, it is not allowed to specify both `ZIP_FL_CENTRAL` and `ZIP_FL_LOCAL` in flags, except when deleting all extra fields (i.e., extra_field_index being `ZIP_EXTRA_FIELD_ALL`).

# RETURN VALUES

Upon successful completion 0 is returned. Otherwise, -1 is returned and the error code in archive is set to indicate the error.

# ERRORS

`zip_file_extra_field_delete`() and `zip_file_extra_field_delete_by_id`() fail if:

[`ZIP_ER_NOENT`]
  index is not a valid file index in archive.

# SEE ALSO

libzip(3), zip_file_extra_field_get(3), zip_file_extra_field_set(3), zip_file_extra_fields_count(3)

# HISTORY

`zip_file_extra_field_delete`() and `zip_file_extra_field_delete_by_id`() were added in libzip 0.11.

# AUTHORS

Dieter Baron <dillo@nih.at> and Thomas Klausner <tk@giga.or.at>

December 18, 2017 | NiH