share (command)

{{Infobox software

| name = share

| logo =

| screenshot =

| screenshot size =

| caption =

| developer = Microsoft, Paragon Technology Systems, DR, Datalight, Novell, Ron Cemer

| released = {{Release year|df=yes|1984}}

| latest release version =

| latest release date =

| operating system = MS-DOS, PTS-DOS, SISNE plus, Windows, DR DOS, ROM-DOS, FreeDOS

| genre = Command

| license =

| website =

}}

In computing, share is a command for DOS that allows software to perform file locks. Locking files became necessary when MS-DOS began allowing files to be accessed simultaneously by multiple programs, either through multitasking or networking.{{Citation

| last1 = Jamsa

| first1 = Kris A.

| title = DOS: The Complete Reference

| publisher = Osborne McGraw-Hill

| page = 206

| year = 1993

| isbn = 0078819040

| url = https://books.google.com/books?id=UW9GAAAAYAAJ

| postscript= .

}}{{cite web|url=http://www.easydos.com/share.html|title=DOS Command: SHARE}}[http://www.computerhope.com/sharehlp.htm MS-DOS and Windows command line share command]

Implementations

On MS-DOS, the command is available in versions 3 and later.{{Cite book|author-last=Wolverton|author-first=Van|title=Running MS-DOS Version 6.22 (20th Anniversary Edition), 6th Revised edition|date=2003|publisher=Microsoft Press|isbn=0-7356-1812-7}} The command is also available in FreeDOS,{{cite web|url=http://www.ibiblio.org/pub/micro/pc-stuff/freedos/files/distributions/1.2/repos/pkg-html/group-base.html |title=FreeDOS 1.2 Updates Group - FreeDOS Base |publisher=Ibiblio.org |date= |accessdate=2022-09-08}} PTS-DOS,

{{cite web |title=PTS-DOS 2000 Pro User Manual |publisher=Paragon Technology GmbH |location=Buggingen, Germany |date=1999 |url=http://download.paragon-software.com/doc/manual_dos_eng.pdf |access-date=2018-05-12 |url-status=live |archive-url=https://web.archive.org/web/20180512094512/http://download.paragon-software.com/doc/manual_dos_eng.pdf |archive-date=2018-05-12}} and SISNE plus.[https://datassette.org/manuais/ibm-pc/sisne-plus-referencia-sumaria SISNE plus - Referência Sumária | Datassette] The FreeDOS version was developed by Ron Cemer and is licensed under the GPL.{{cite web|url=http://www.ibiblio.org/pub/micro/pc-stuff/freedos/files/distributions/1.2/repos/pkg-html/share.html |title=FreeDOS 1.2 Updates Package - share (FreeDOS Base) |publisher=Ibiblio.org |date=2007-10-20 |accessdate=2022-09-08}} DR DOS 6.0[https://www.4corn.co.uk/archive/docs/DR%20DOS%206.0%20User%20Guide-opt.pdf DR DOS 6.0 User Guide Optimisation and Configuration Tips] and Datalight ROM-DOS{{cite web|url=https://www.datalight.com/assets/files/ROM-DOS_Users_Guide.pdf|title=Datalight ROM-DOS User's Guide|website=www.datalight.com}} include an implementation of the {{code|share}} command.

Windows XP and later versions include 16-bit commands (nonnative) for the MS-DOS subsystem that are included to maintain MS-DOS compatibility. The share MS-DOS subsystem command performs functions that are now inherent to Microsoft Windows. It is available to preserve compatibility with existing files, but has no effect at the command line because the functionality is automatic. The 16-bit MS-DOS subsystem commands are not available on 64-bit editions of Windows.[https://docs.microsoft.com/en-us/previous-versions/windows/it-pro/windows-xp/bb490895(v%3dtechnet.10) MS-DOS subsystem commands]

Design

There were five locking modes:

Deny None
Deny Read
Deny Write
Deny All
Compatibility (designed for backward compatibility with existing MS-DOS programs)

The program runs as a terminate-and-stay-resident program and is typically loaded at boot-up.

Syntax

share [/F:space] [/L:locks]

/F:space Allocates file space (in bytes) for file-sharing information.
/L:locks Sets the number of files that can be locked at one time.

share (command)

Implementations

Design

Syntax

See also

References

Further reading