Using revision specifiers

File specifiers can be modified by appending # or @ to them.

The # and @ specifiers refer to specific revisions of files as stored in the depot:

Modifier	Meaning
`file#n`	Revision specifier: The `n`th revision of `file`.
`file#none` `file#0`	The nonexistent revision: If a revision of `file` exists in the depot, it is ignored. This is useful when you want to remove a file from the client workspace while leaving it intact in the depot, as in `p4 syncfile#none`. The filespec `#0` can be used as a synonym for `#none` - the nonexistent revision can be thought of as the one that "existed" before the first revision was submitted to the depot.
`file#head`	The head revision (latest version) of `file`. Except where explicitly noted, this is equivalent to referring to the file without a revision specifier.
`file#have`	The revision on the current client: the revision of file last `p4 sync`ed into the client workspace.
`file@n`	Change number: The revision of `file` immediately after changelist `n` was submitted.
`file@=n`	Change number: The revision of `file` at the specified changelist number `n`. `n` can be a submitted or a shelved change number; it can’t be a pending (non-shelved) change number.
`file@labelname`	Label name: The revision of `file` in the label `labelname`.
`file@clientname`	Client name: The revision of `file` last taken into client workspace `clientname`. Note that deleted files (that is, files marked for `delete` at their latest revision) are not considered to be part of a workspace.
`file@datespec`	Date and time: The revision of `file` at the date and time specified. If no time is specified, the head revision at 00:00:00 on the morning of the date specified is returned. Dates are specified `yyyy/mm/dd:hh:mm:ss` or `yyyy/mm/ddhh:mm:ss` (with either a space or a colon between the date and the time). The datespec `@now` can be used as a synonym for the current date and time.

Revision specifiers can be used to operate on many files at once: p4 sync //myclient/...#4 copies the fourth revision of all non-open files into the client workspace.

If specifying files by date and time (that is, using specifiers of the form file@datespec), the date specification should be parsed by your local shell as a single token. You may need to use quotation marks around the date specification if you use it to specify a time as well as a date.

Files that have been shelved can also be accessed with the p4 diff, p4 diff2, p4 files, and p4 print commands, using the revision specifier @=change, where change is the pending changelist number.

Some Perforce file specification characters may be intercepted and interpreted by the local shell, and need to be escaped before use. For instance, # is used as the comment character in most UNIX shells, and / may be interpreted by (non-Perforce) DOS commands as an option specifier. File names with spaces in them may have to be quoted on the command line.

For information on these and other platform-specific issues, see the release notes for your platform.