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The default behavior with no options is to extract into the current directory and subdirectories below it all files from the specified ZIP archive. Where the source is on an NTFS volume and target does not exist, a file symbolic link will be created.
If the first option on the command line is -Zthe remaining options are taken to be zipinfo options. See the appropriate manual page for a description of these options. This option is similar to the -p option except that the name of each file is printed as it is extracted, the -a option is allowed, and ASCII-EBCDIC conversion is automatically performed if appropriate.
This option is not listed in the unzip usage screen. By default unzip queries before overwriting, but the -o option may be used to suppress the queries. Note that under many operating systems, the TZ timezone environment variable must be set correctly in order for -f and -u to work properly under Unix the variable is usually set automatically.
The names, uncompressed file sizes and modification dates and times of the specified files are printed, along with totals for all files specified. In addition, the zipfile comment and individual file comments if any are displayed. Nothing but the file data is sent to stdout, and the files are how to deposit with binary compare two files in c++ extracted in binary format, just as they are stored no conversions.
This option extracts each specified file in memory and compares the CRC cyclic redundancy check, an enhanced checksum of the expanded file with the original file's stored CRC value. This corresponds to zip 's -go option except that it can be used on wildcard zipfiles e. This option performs the same function as the -f option, extracting with query files that are newer than those with the same name on disk, and in addition it extracts those files that do not already exist on disk.
See -f above for information on setting the timezone properly. This option has evolved and now behaves as both an option and a modifier. As an option it has two purposes: In contrast to most of the competing utilities, unzip removes the 12 additional header bytes of encrypted entries from the compressed size numbers. Therefore, compressed size and compression ratio figures are independent of the entry's encryption status and show the correct compression performance.
The complete size of the encrypted compressed data stream for zipfile entries is reported by the more verbose zipinfo reports, see the separate manual. As a modifier it how to deposit with binary compare two files in c++ in conjunction with other how to deposit with binary compare two files in c++ e. The -aa option forces all files to be extracted as text, regardless of the supposed file type.
On VMS, see also -S. This is a shortcut for -a. The backup file is gets the name of the target file with a tilde and optionally a unique sequence number up to 5 digits appended. The sequence number is applied whenever another file with the original name plus tilde already exists. When used together with the "overwrite all" option -onumbered backup files are never created. In this case, all backup files are named as the original file with an appended tilde, existing backup files are deleted without notice.
This feature works similarly to the default behavior of emacs in many locations. Users should be aware that the -B option does not prevent loss of existing data under all circumstances. When this rename attempt fails because of a file locks, insufficient privileges, or A similar scenario takes place when the sequence number range for numbered backup files gets exhaustedor for bit systems.
In this case, the backup file with the maximum sequence number is deleted and replaced by the new backup version without notice. Because some file systems are fully case-sensitive notably those under the Unix operating system and because both ZIP archives and unzip itself are portable how to deposit with binary compare two files in c++ platforms, unzip 's default behavior is to match both wildcard and literal filenames case-sensitively.
The -C option affects file specs in both the normal file list and the excluded-file list xlist. Please note that the -C option does neither affect the search for the zipfile s nor the matching of archive entries to existing files on the extraction path. Normally, unzip tries to restore all meta-information for extracted items that are supplied in the Zip archive and do not require privileges or impose a security risk.
By specifying -Dunzip is told to suppress restoration of timestamps for directories explicitly created from Zip archive entries. The duplicated option -DD forces suppression of timestamp restoration for all extracted entries files and directories. This option results in setting the timestamps for all extracted entries to the current time. To enable restoration of directory timestamps, the negated option --D should be specified. Here, a single -D on the command line combines with the default -D to do what an explicit -DD does how to deposit with binary compare two files in c++ other systems.
When the stored filename appears to already have an appended NFS filetype extension, it is replaced by the info from the extra field. Instead, the most compatible filename stored in the generic part of the entry's header is used. The archive's directory structure is not recreated; all files are deposited in the extraction directory by default, the current one.
All Macintosh specific info is skipped. Data-fork and resource-fork are restored as separate files. Without this flag, these attribute bits are cleared for security reasons.
This was unzip 's default behavior in releases prior to 5. By default unzip lists and extracts such filenames exactly as they're stored excepting truncation, conversion of unsupported characters, etc. The -LL option forces conversion of every filename to lowercase, regardless of the originating file system. Unlike Unix morethere is no forward-searching or editing capability.
Also, unzip doesn't notice if long lines wrap at the edge of the screen, effectively resulting in the printing of two or more lines and the likelihood that some text will scroll off the top of the screen before being viewed. On some how to deposit with binary compare two files in c++ the number of available lines on the screen is not detected, in which case unzip assumes the height is 24 lines.
If a file already exists, skip the extraction of that file without prompting. By default unzip queries before extracting any file that already exists; the user may choose to overwrite only the current file, overwrite all files, skip extraction of the current file, skip extraction of all existing files, or rename how to deposit with binary compare two files in c++ current file.
File comments are created with the -c option of zipor with the -N option of the Amiga port of zipwhich stores filenotes as comments. This is a dangerous option, so use it with how to deposit with binary compare two files in c++. Many multi-user operating systems including PTC MKS Toolkit on Windows provide ways for any user to see the current command line of any other user; even on stand-alone systems there is always the threat of over-the-shoulder peeking.
Storing the plaintext password as part of a command line in an automated script is even worse. Whenever possible, use the non-echoing, interactive prompt to enter passwords.
And where security is truly important, use strong encryption such as Pretty Good Privacy instead of the relatively weak encryption provided by standard zipfile utilities. Ordinarily unzip prints the names of the files it's extracting or testing, the extraction methods, any file or zipfile comments that may be stored in the archive, and possibly a summary when finished with each archive. The -q[q] options suppress the printing of some or all of these messages.
Since all PC operating systems allow spaces in filenames, unzip by default extracts filenames with spaces intact e. This can be awkward, however, since MS-DOS in particular does not gracefully support spaces in filenames.
Conversion of spaces to underscores can eliminate the awkwardness in some cases. This option is mainly provided for debugging purpose when the fairly new UTF-8 support is suspected to mangle up extracted filenames.
The handling of filename codings within unzip falls back to the behaviour of previous versions. VMS files can be stored with a version number, in the format file. On file systems that limit filenames to particularly short lengths, the version numbers may be truncated or stripped regardless of this option. Currently, UnZip uses the same pattern matching rules for both wildcard zipfile specifications and zip entry selection patterns in most ports.
In most cases this will require special system privileges, and doubling the option -XX under NT instructs unzip to use privileges for how to deposit with binary compare two files in c++ but under Unix, for example, a user who belongs to several groups can restore files owned by any of those groups, as long as the user IDs match his or her own. Note that ordinary file attributes are always restored--this option applies only to optional, extra ownership info available on some operating systems.
It is not clear under what conditions this would ever be useful anyway. The default is to treat them as file types. By default, volume labels are ignored. This safety feature new for version 5. To achieve this, it is necessary to set the extraction target folder to root e.
However, when the -: Use this option with extreme caution. Generally, this allows to embed ASCII control characters or even sophisticated control sequences in file names, at least on 'native' Unix file systems. However, it may be highly suspicious to make use of this Unix "feature". Embedded control characters in file names might have nasty side effects when displayed on screen by some listing code without sufficient filtering.
And, for ordinary users, it may be difficult to handle such file names e. Therefore, unzip applies a filter by default that removes potentially dangerous control characters from the extracted file names. The default is to exploit the destination file system, preserving case and extended file name characters on an ODS5 destination file system; and applying the ODS2-compatibility file name filtering on an ODS2 destination file system. This can be done with any option, but it is probably most useful with the -a-L-C-qhow to deposit with binary compare two files in c++or -n modifiers: For example, to make unzip act as quietly as possible, only reporting errors, one would use one of the following commands:.
Environment options are, in effect, considered to be just like any other command-line options, except that they are effectively the first options on the command line. For instance, to override one of the quiet-flags in the example above, use the command. The first hyphen is the normal switch character, and the second is a minus sign, acting on the q option.
Thus the effect here is to cancel one quantum of quietness. To cancel both quiet flags, two or more minuses may be used:. This may seem awkward or confusing, but it is reasonably intuitive: It is also consistent with the behavior how to deposit with binary compare two files in c++ Unix nice.
The timezone variable TZ should be set according to the local timezone in order for the -f and -u to operate correctly. See the description of -f above for details. This variable may also be necessary to get timestamps of extracted files to be set correctly.