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# funzip - Unix, Linux Command

# NAME

funzip - filter for extracting from a ZIP archive in a pipe

# SYNOPSIS

funzip [-password] [input[.zip|.gz]]

# ARGUMENTS

Tag | Description
--- | ---
[-password] | Optional password to be used if ZIP archive is encrypted. Decryption may not be supported at some sites. See DESCRIPTION for more details.
[input[.zip|.gz]] | Optional input archive file specification. See DESCRIPTION for details.

# DESCRIPTION

funzip without a file argument acts as a filter; that is, it assumes that a ZIP archive (or a gzip’d(1) file) is being piped into standard input, and it extracts the first member from the archive to stdout. When stdin comes from a tty device, funzip assumes that this cannot be a stream of (binary) compressed data and shows a short help text, instead. If there is a file argument, then input is read from the specified file instead of from stdin.

A password for encrypted zip files can be specified on the command line (preceding the file name, if any) by prefixing the password with a dash. Note that this constitutes a security risk on many systems; currently running processes are often visible via simple commands (e.g., ps(1) under Unix), and command-line histories can be read. If the first entry of the zip file is encrypted and no password is specified on the command line, then the user is prompted for a password and the password is not echoed on the console.

Given the limitation on single-member extraction, funzip is most useful in conjunction with a secondary archiver program such as tar(1). The following section includes an example illustrating this usage in the case of disk backups to tape.

# EXAMPLES

To use funzip to extract the first member file of the archive test.zip and to pipe it into more(1):

    funzip test.zip | more

To use funzip to test the first member file of test.zip (any errors will be reported on standard error):

    funzip test.zip > /dev/null

To use zip and funzip in place of compress(1) and zcat(1) (or gzip(1L) and gzcat(1L)) for tape backups:

    tar cf - . | zip -7 | dd of=/dev/nrst0 obs=8k
    dd if=/dev/nrst0 ibs=8k | funzip | tar xf -

(where, for example, nrst0 is a SCSI tape drive).

# BUGS

When piping an encrypted file into more and allowing funzip to prompt for password, the terminal may sometimes be reset to a non-echo mode. This is apparently due to a race condition between the two programs; funzip changes the terminal mode to non-echo before more reads its state, and more then ‘‘restores’’ the terminal to this mode before exiting. To recover, run funzip on the same file but redirect to /dev/null rather than piping into more; after prompting again for the password, funzip will reset the terminal properly.

There is presently no way to extract any member but the first from a ZIP archive. This would be useful in the case where a ZIP archive is included within another archive. In the case where the first member is a directory, funzip simply creates the directory and exits.

The functionality of funzip should be incorporated into unzip itself (future release).

# SEE ALSO

zipcloak(1L), zipinfo(1L), zipnote(1L), zipsplit(1L)

# URL

The Info-ZIP home page is currently at

    http://www.info-zip.org/pub/infozip/

or

    ftp://ftp.info-zip.org/pub/infozip/ .

# AUTHOR

Mark Adler (Info-ZIP)

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