.TH "alpm-epoch" 7

.SH "NAME"
.PP
epoch \- version prefix to enforce a higher version consideration for ALPM based packages\.

.SH "DESCRIPTION"
.PP
The \fBepoch\fP format is a version format, that is used as prefix to \fBpkgver\fP in a composite version string\.
This format is used in build scripts or file formats for package data description or reproduction to indicate, that a composite version is to be considered newer than one without or a lower \fBepoch\fP component\.
This enables package maintainers to release downgraded versions of a package if needed\.
.PP
The \fBepoch\fP value is represented by a non\-negative integer and is considered to default to '0' if unset\.
.PP
When used in a composite version string, \fBepoch\fP is directly followed by a ':' sign and the \fBpkgver\fP\.
.PP
If two composite version strings are sorted, they are first sorted based on their \fBepoch\fP component and only afterwards based on their \fBpkgver\fP component\.
.PP
As general rule, the sorting precedence is: `\f[CR]epoch > pkgver\fP`\.

.SH "EXAMPLES"
.PP
The explicit `\f[CR]1\fP` \fBepoch\fP component in the right hand composite version string overrules the implicit `\f[CR]0\fP` \fBepoch\fP component of the left hand composite version string\.
Since the \fBepoch\fP takes precedence, `\f[CR]1:0\.9\.0\fP` is considered "newer" than `\f[CR]1\.0\.0\fP` even though the upstream version represented by the \fBpkgver\fP component is older\.
.RS
.PP
.nf
"1\.0\.0" < "1:0\.9\.0"
.fi
.RE
.PP
Composite version strings with the same \fBpkgver\fP component are also sorted according to their \fBepoch\fP component first\.
.RS
.PP
.nf
"1:1\.0\.0" < "2:1\.0\.0"
.fi
.RE

.SH "SEE ALSO"
.PP
\fBBUILDINFO\fP(5), \fBPKGBUILD\fP(5), \fBPKGINFO\fP(5), \fBSRCINFO\fP(5), \fBalpm\-package\-version\fP(7), \fBalpm\-pkgrel\fP(7), \fBalpm\-pkgver\fP(7), \fBvercmp\fP(8)