1 UNZIPSFX unzipsfx - self-extracting stub for prepending to ZIP archives [-cfptuz[ajnoqsCLV$]] [file(s) ...] [-x xfile(s) ...] unzipsfx is a modified version of unzip designed to be prepended to existing ZIP archives in order to form self- extracting archives. Instead of taking its first non-flag argument to be the zipfile(s) to be extracted, unzipsfx seeks itself under the name by which it was invoked and tests or extracts the contents of the appended archive. Because the executable stub adds bulk to the archive (the whole purpose of which is to be as small as possible), a number of the regular version's less-vital capabilities have been removed. Among these are the usage (or help) screen, the listing and diagnostic functions (-l and -v), the abil- ity to decompress older compression formats (the ``reduce,'' ``shrink'' and ``implode'' methods), and the ability to extract to a directory other than the current one. Decryp- tion is supported as a compile-time option but should be avoided unless the attached archive contains encrypted files. Note that self-extracting archives made with unzipsfx are no more (or less) portable across different operating systems than is the unzip executable itself. In general a self- extracting archive made on a particular Unix system, for example, will only self-extract under the same flavor of Unix. Regular unzip may still be used to extract the embed- ded archive as with any normal zipfile, although it will generate a harmless warning about extra bytes at the begin- ning of the zipfile. [file(s)] An optional list of archive members to be processed. Regular expressions (wildcards) similar to those in Unix egrep(1) may be used to match multiple members. These wildcards may contain: * matches a sequence of 0 or more characters ? matches exactly 1 character [...] matches any single character found inside the brackets; ranges are specified by a beginning character, a hyphen, and an ending character. If an exclamation point or a caret (`!' or `^') fol- lows the left bracket, then the range of charac- ters within the brackets is complemented (that is, anything except the characters inside the brackets is considered a match). (Be sure to quote any character which might otherwise be interpreted or modified by the operating system, particularly under Unix and VMS.) [-x xfile(s)] An optional list of archive members to be excluded from processing. Since wildcard characters match directory separators (`/'), this option may be used to exclude any files which are in subdirectories. For example, ``unzip foo *.[ch] -x */*'' would extract all C source files in the main directory, but none in any subdirec- tories. Without the -x option, all C source files in all directories within the zipfile would be extracted. 2 Options unzipsfx supports the following unzip options: -c and -p (extract to standard output/screen), -f and -u (freshen and update existing files upon extraction), -t (test archive) and -z (print archive comment). All normal listing options (-l, -v and -Z) have been removed, but the testing option (-t) may be used as a ``poor man's'' listing. Alter- natively, those creating self-extracting archives may wish to include a short listing in the zipfile comment. See unzip for a more complete description of these options. MODIFIERS unzipsfx currently supports all unzip modifiers: -a (convert text files), -n (never overwrite), -o (overwrite without prompting), -q (operate quietly), -C (match names case-insenstively), -L (convert uppercase-OS names to lower- case), -j (junk paths) and -V (retain version numbers); plus the following operating-system specific options: -X (restore VMS owner/protection info), -s (convert spaces in filenames to underscores [DOS, OS/2, NT]) and -$ (restore volume label [DOS, OS/2, NT, Amiga]). (Support for regular ASCII text-conversion may be removed in future versions, since it is simple enough for the archive's creator to ensure that text files have the appropriate for- mat for the local OS. EBCDIC conversion will of course con- tinue to be supported since the zipfile format implies ASCII storage of text files.) See unzip for a more complete description of these modifiers. 2 Environment_options unzipsfx uses the same environment variables as unzip does, although this is likely to be an issue only for the person creating and testing the self-extracting archive. See unzip for details. 2 Decryption Decryption is supported exactly as in unzip; that is, interactively with a non-echoing prompt for the password(s). See unzip for details. Once again, note that if the archive has no encrypted files there is no reason to use a version of unzipsfx with decryption support; that only adds to the size of the archive. 2 Examples To create a self-extracting archive letters from a regular zipfile letters.zip and change the new archive's permissions to be world-executable under Unix: cat unzipsfx letters.zip > letters chmod 755 letters To create the same archive under MS-DOS, OS/2 or NT (note the use of the /b [binary] option to the copy command): copy /b unzipsfx.exe+letters.zip letters.exe Under VMS: copy unzipsfx.exe,letters.zip letters.exe letters == "$currentdisk:[currentdir]letters.exe" (The VMS append command may also be used. The second com- mand installs the new program as a ``foreign command'' capa- ble of taking arguments.) To test (or list) the newly created self-extracting archive: letters -t To test letters quietly, printing only a summary message indicating whether the archive is OK or not: letters -tq To extract the complete contents into the current directory, recreating all files and subdirectories as necessary: letters To extract only the README file to standard output (the screen): letters -c README To print only the zipfile comment: letters -z 2 Limitations The principle and fundamental limitation of unzipsfx is that it is not portable across architectures or operating sys- tems, and therefore neither are the resulting archives. For some architectures there is limited portability, however (e.g., between some flavors of Intel-based Unix). unzipsfx has no knowledge of the user's PATH, so in general an archive must either be in the current directory when it is invoked, or else a full or relative path must be given. If a user attempts to extract the archive from a directory in the PATH other than the current one, unzipsfx will print a warning to the effect, ``can't find myself.'' This is always true under Unix and may be true in some cases under MS-DOS, depending on the compiler used (Microsoft C fully qualifies the program name, but other compilers may not). Under OS/2 and NT there are operating-system calls available which provide the full path name, so the archive may be invoked from anywhere in the user's path. The situation is not known for Atari TOS, MacOS, etc. As noted above, a number of the normal unzip functions have been removed in order to make unzipsfx smaller: usage and diagnostic info, listing functions and extraction to other directories. Also, only stored and deflated files are supported. The latter limitation is mainly relevant to those who create SFX archives, however. VMS users must know how to set up self-extracting archives as foreign commands in order to use any of unzipsfx's options. This is not necessary for simple extraction, but the command to do so then becomes, e.g., ``run letters'' (to continue the examples given above). unzipsfx is not supported on the Amiga because of the way the loader works; the entire archive contents would be loaded into memory by default. It may be possible to work around this by defining the attached archive to be a ``debug hunk,'' but compatibility problems between the ROM levels of older Amigas and newer ones are likely to cause problems regardless. All current bugs in unzip exist in unzipsfx as well. 2 Diagnostics unzipsfx's exit status (error level) is identical to that of unzip; see the corresponding man page. 2 See_also funzip, unzip, zip, zipcloak, zipgrep, zipinfo, zipnote, zipsplit 2 Authors Greg Roelofs was responsible for the basic modifications to UnZip necessary to create UnZipSFX. See unzip for the current list of zip-bugs authors, or the file CONTRIBS in the UnZip source distribution for the full list of Info-ZIP contributors.