| ZIP_OPEN(3) | Library Functions Manual | ZIP_OPEN(3) |

NAME

zip_open, zip_open_from_source — open zip archive

LIBRARY

libzip (-lzip)

SYNOPSIS

#include <zip.h>

zip_t *
zip_open(const char *path, int flags, int *errorp);

zip_t *
zip_open_from_source(zip_source_t *zs, int flags, zip_error_t *ze);

DESCRIPTION

The zip_open() function opens the zip archive specified by path and returns a pointer to a struct zip, used to manipulate the archive. The flags are specified by or'ing the following values, or 0 for none of them.

ZIP_CHECKCONSPerform additional stricter consistency checks on the archive, and error if they fail.ZIP_CREATECreate the archive if it does not exist.ZIP_EXCLError if archive already exists.ZIP_TRUNCATEIf archive exists, ignore its current contents. In other words, handle it the same way as an empty archive.ZIP_RDONLYOpen archive in read-only mode.

If an error occurs and errorp is non-NULL, it will be set to the corresponding error code.

The zip_open_from_source() function opens a zip archive encapsulated by the zip_source zs using the provided flags. In case of error, the zip_error ze is filled in.

RETURN VALUES

Upon successful completion zip_open() and zip_open_from_source() return a struct zip pointer. Otherwise, NULL is returned and zip_open() sets *errorp to indicate the error, while zip_open_from(source) sets ze to indicate the error.

CAVEATS

Opening the same archive multiple times can lead to problems: When a modified archive is closed, the underlying file is rewritten and thus invalidates all other zip_t objects for that archive, which will fail in unpredictable ways. Also, writing may fail on some platforms if the file is in use by another zip_t object.

Thus, it is only valid to open the same archive multiple times as long as you make changes to at most one zip_t object and close that last. Using the flag ZIP_RDONLY helps enforce that.

EXAMPLES

Here's an example of how you could report errors during zip_open:

zip_t *za;
    int err;

    if ((za = zip_open(name, 0, &err)) == NULL) {
        zip_error_t error;
        zip_error_init_with_code(&error, err);
        fprintf(stderr, "%s: cannot open zip archive '%s': %s\n",
	        progname, name, zip_error_strerror(&error));
        zip_error_fini(&error);
        return -1;
    }

ERRORS

The archive specified by path is opened unless:

[ZIP_ER_EXISTS]The file specified by path exists and ZIP_EXCL is set.[ZIP_ER_INCONS]Inconsistencies were found in the file specified by path. This error is often caused by specifying ZIP_CHECKCONS but can also happen without it.[ZIP_ER_INVAL]The path argument is NULL.[ZIP_ER_MEMORY]Required memory could not be allocated.[ZIP_ER_NOENT]The file specified by path does not exist and ZIP_CREATE is not set.[ZIP_ER_NOZIP]The file specified by path is not a zip archive.[ZIP_ER_OPEN]The file specified by path could not be opened.[ZIP_ER_READ]A read error occurred; see errno for details.[ZIP_ER_SEEK]The file specified by path does not allow seeks.For newly created archives, zip_open() does not try to create the file; this is done when calling zip_close(3) and any errors, like missing write permissions, will be reported then.

HISTORY

zip_open() and zip_open_from_source() were added in libzip 1.0.

AUTHORS

Dieter Baron <[email protected]> and Thomas Klausner <[email protected]>

| September 16, 2025 | NiH |