# -t (set Type of archive) switch

Specifies the type of archive.

#### Syntax

    -t{archive_type}[:s{Size}][:r][:e][:a]

{archive_type}
  Specifies the type of archive. It can be: *, #, 7z, xz, split, zip, gzip, bzip2, tar, ....
*:r
  Default mode. 7-Zip opens archive and subfile, if it's supported by format.
*
  Opens only one top level archive.
*:s{Size}[b | k | m | g]
  Sets upper limit for start of archive position. Default scan size is 8 MBytes "*:s8m". Example: "*:s0" means that it will open only file that has no any stub before archive.
#
  Opens file in Parser mode, and ignores full archives.
#:a
  Same as *, but it opens files with unknown extensions that contain archives in Parser Mode.
#:e
  Opens file in Parser mode and checks all byte positions as start of archive.

If -t{archive_type} switch is not specified, 7-Zip uses extension of archive filename to detect the type of archive. If you create new archive, -t{archive_type} switch is not specified and there is no extension of archive, 7-Zip will create .7z archive.

If -t{archive_type} switch is not specified and archive name contains incorrect extension, the program will show the warning.

It's possible to use the combined type (for example, mbr.vhd) for "Extract" and "List" commands for some archives.

When you extract archive of some types that contains another archive without compression (for example, MBR in VHD), 7-Zip can open both levels in one step. If you want to open/extract just top level archive, use -t* switch.

Note: xz, gzip and bzip2 formats support only one file per archive. If you want to compress more than one file to these formats, create a tar archive at first, and then compress it with your selected format.

Note: -thash specifies special "hash" type, where the archive file contains only file name paths and hash (sha-256 or another) checksums. But that hash file doesn't contain real data content of files.

#### Example

    7z a -tzip archive.zip *.txt

adds all *.txt files from current directory to zip archive archive.zip.

    7z a -thash list.sha256 *.txt

creates list.sha256 file for *.txt files.

    7z t -t7z.split archive.7z.001

tests all files in archive.7z.001. It also checks that archive is multivolume .7z archive.

    7z x -t# sfxarchive.exe

extracts sfxarchive.exe in parser mode.

    7z x -tiso archive.iso

extracts files from archive.iso open as ISO archive.

    7z x -tudf archive.iso

extracts files from archive.iso open as ISO archive.

    7z a -thash file.sha256 *.txt

creates hash file file.sha256 with SHA-256 checksums for all *.txt files.

    7z t -thash file.sha256 -shd.

checks hash file file.sha256 over files stored in current folder.

#### Commands that can be used with this switch

a (Add), d (Delete), e (Extract), l (List), t (Test), u (Update), x (Extract with full paths)