mirrors/tar
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

doc: mention timestamp limits

Browse Source
This commit is contained in:
Paul Eggert
2025-01-29 11:56:04 -08:00
parent 2e41cdce6d
commit 31d84e2f67
1 changed files with 21 additions and 12 deletions
Download Patch File Download Diff File Expand all files Collapse all files

33
doc/tar.texi
View File

@@ -9617,6 +9617,10 @@ File names and symbolic links can contain at most 100 bytes.
@item
File sizes must be less than 8 GiB (@math{2^33} bytes = 8,589,934,592 bytes).
@item
File timestamps must be nonnegative and less than @math{2^33} seconds
since the Epoch, corresponding to the range from 1970-01-01 00:00:00
(inclusive) to 2242-03-16 12:56:32 (exclusive) UTC, ignoring leap seconds.
@item
It is impossible to store special files (block and character
devices, fifos etc.)
@item
@@ -9647,7 +9651,11 @@ So, in most cases file names must be a bit shorter than 255 bytes.
@item
Symbolic links can contain at most 100 bytes.
@item
Files can contain at most 8 GiB (@math{2^33} bytes = 8,589,934,592 bytes).
File sizes must be less than 8 GiB (@math{2^33} bytes = 8,589,934,592 bytes).
@item
File timestamps must be nonnegative and less than @math{2^33} seconds
since the Epoch, corresponding to the range from 1970-01-01 00:00:00
(inclusive) to 2242-03-16 12:56:32 (exclusive) UTC, ignoring leap seconds.
@item
UIDs, GIDs, device major numbers, and device minor numbers
must be less than @math{2^21} (2,097,152).
@@ -9655,18 +9663,19 @@ must be less than @math{2^21} (2,097,152).
@item star
The format used by the late J@"org Schilling's @command{star}
implementation. @GNUTAR{} is able to read @samp{star} archives but
currently does not produce them.
implementation. @GNUTAR{} can read @samp{star} archives but
does not produce them.
@item posix
The format defined by @acronym{POSIX.1-2001} and later. This is the
most flexible and feature-rich format. It does not impose arbitrary
restrictions on file sizes or file name lengths. This format is more
restrictions on file sizes or timestamps or file name lengths.
This format is more
recent, so some @command{tar} implementations cannot handle it properly.
However, any @command{tar} implementation able to read @samp{ustar}
archives should be able to read most @samp{posix} archives as well,
except that it will extract any additional information (such as long
file names) as extra plain text files.
file names) as extra plain text files and their parent directories.
This archive format will be the default format for future versions
of @GNUTAR{}.
@@ -9676,13 +9685,13 @@ of @GNUTAR{}.
The following table summarizes the limitations of each of these
formats:
@multitable @columnfractions .10 .20 .20 .20 .20
@headitem Format @tab UID @tab File Size @tab File Name @tab Devn
@item gnu @tab 1.8e19 @tab Unlimited @tab Unlimited @tab 63
@item oldgnu @tab 1.8e19 @tab Unlimited @tab Unlimited @tab 63
@item v7 @tab 2097151 @tab 8 GiB @minus{} 1 @tab 99 @tab n/a
@item ustar @tab 2097151 @tab 8 GiB @minus{} 1 @tab 255 @tab 21
@item posix @tab Unlimited @tab Unlimited @tab Unlimited @tab Unlimited
@multitable {Format} {no limit} {File Size} {File Date} {File Name} {no limit}
@headitem Format @tab UID @tab File Size @tab File Date @tab File Name @tab Devn
@item gnu @tab 1.8e19 @tab no limit @tab no limit @tab no limit @tab 63
@item oldgnu @tab 1.8e19 @tab no limit @tab no limit @tab no limit @tab 63
@item v7 @tab 2097151 @tab < 8 GiB @tab 1970--2242 @tab 99 @tab n/a
@item ustar @tab 2097151 @tab < 8 GiB @tab 1970--2242 @tab 255 @tab 21
@item posix @tab no limit @tab no limit @tab no limit @tab no limit @tab no limit
@end multitable
The default format for @GNUTAR{} is defined at compilation