- vcheck
vcheck [options]
vcheck
For a complete list of command line options, run
$ vcheck --help
- vcheck
- "
" - a regular expression names have to match
- ""
- a minimal urgency (which can be defined on a per-program basis, as levels
of high
, medium, and low) - ""
- those programs which haven't yet been downloaded since a new latest version was found
- ""
- those programs which previous queries failed for (optionally, a certain minimum number of times)
- ""
- a conjunctive combination of several of these conditions
In case you're behind a firewall, an HTTP(-based) proxy can be defined in a number of ways (precendence in this order): - ""
- a specific HTTP or FTP proxy, respectively, defined in the config file
- ""
- a common HTTP+FTP proxy defined in the config file
- ""
- a specific HTTP or FTP proxy, defined via the environment variables
$http_proxy
/$HTTP_PROXY and $ftp_proxy /$FTP_PROXY, respectively (each in this order of precendence) vcheck
uses ANSI escape sequences to visually enhance its output. Success messages are usually printed in green, error messages are yellow or red (signalling severity). This feature can be disabled temporarily by using the corresponding command line switch, or permanently, via a setting in the configuration file (see "CONFIGURATION SECION").
$ vcheck --grammar
Details about both the grammar in general and the meaning of involved keyword can be found in "GRAMMAR". An example of what a config file looks like in principle can be found in "EXAMPLES".
The basic purpose of vcheck
- When run as
- "Boolean"
- Keywords of this type set a property based on their mere presence. An example
of this is the config
section field dldefaultno:
config = {
dldefaultno
}
- "string"
- String fields consist of a keyword followed by an equal sign (`=') and a string
representing the field's value. If the string value contains white space or
(double) quotation marks, it needs to be surrounded by (double) quotation marks
(`"'). In this case, both quotation marks inside the string and backslashes
need to be escaped by backslashes (`\'). Note that string values may not span
several lines but have to be contained on a single one, and there may be
validation rules as to what the value may be like. Besides, string fields
are typically required to be of non-zero length.
An example of this type of field is the prog
section field comment:
prog foo = {
[...]
comment = Hello!
comment = "Comment with white space and \"quotes\"!"
[...]
}
- "string
- String enumerations are basically string fields with but a limited set
of allowed values. An example of this is the prog
section field dl, whose value must be either "yes" or "no", if present:
prog foo = {
[...]
dl = yes
[...]
}
vcheck --grammar
vcheck
Section data is a sequence of settings, or fields, of a number of types, some of which are obligatory while others are optional, separated by white space (typically, line feeds, to keep things readable). There are the following types of fields:
- The configuration section is optional and, if present, contains settings
globally affecting vcheck
- "defaulturgency
- Specifies the checking urgency level to assume, unless specified otherwise in
a program's record via prog.urgency
. Urgencies allow for a crude selection of programs to check for via the "--urgency" command line parameter. In absence of this option, the default urgency is medium. - "deleteold
- If included in the config
section, causes the script to automatically look for and delete versions of a program obsoleted by a new download. May be overridden by prog.deleteold. See the latter for details.Special note: Use at your own risk! - "dldefaultno
- By default, don't download. This causes the script to download only those
programs whose dl
option is explicitly set to yeswhen run with the "--download" parameter. - "dldir
- This option specifies an absolute
path (i.e., relative to the root directory) of a directory where to put downloaded files. If the download directory isn't set via this or even more explicitly via a prog.dldiroption, downloads will end up in that directory in which the script is executing. - "dlexec
- Specifies a command to be executed after any successful download (unless
overridden for a particular program via prog.dlexec
). A successful download in this context is one whose file type has been recognized and whose integrity could be confirmed. In unizoid environments, the command is executed under whatever shell the environment variable $SHELL defines. The command string is subject to expansion of the following placeholders (see " PLACEHOLDERS" for their meaning): "__DLURL__", "__FILE__" , "__NEWVER__" , "__PROG__" , "__RAWVER__" , "__URL__" . Additionally, `~/' will be replaced by the user's home directory. config.dlexecmay prove useful to, e.g., automatically convert, say, gzipped to bzipped files using a helper script, or to log downloads (see " HINTS"). - "dlprefs
- A semicolon- (`;'-) separated list of Perl-style regular expressions
defining download preferences. Each of the regular expressions is supposed
to match a particular file type that's possible or likely to be encountered.
The order in which the expressions occur defines their precedence (the first
matching expression will determine which of a set of available file types
of a given program version will be selected for download). This value is
the default in effect unless specific preferences are defined on a per-program
basis using prog.dlprefs
. If neither config.dlprefsnor prog.dlprefsis set, the file to be downloaded is chosen pseudo-randomly, if multiple pattern matches occur. For these download preferences to make any sense, file- and version-matching expressions need to be sufficiently non-restrictive to match several possible extensions. For example, "foo-( "__VER__" )\\.t" will match both ".tar.gz" and ".tar.bz2" files, and setting dlprefsto "\\.tar\\.bz2$;\\.tar\\.gz$" will cause the script to preferrably download ".tar.bz2" files. - "dlretry
- The number of times to retry downloading after a failed download. If this option isn't specified, the number of retries defaults to 0. A retry is considered to have failed if either the connection failed, the retrieved document was empty, or the file type has been recognized and its integrity verified.
- "eagerquote
- If this option is set, all string parameters of configuration file options will be surrounded by double quotes. The default is to use quotes only where necessary (e.g., for string parameters containing white space).
- "echoexec
- If this option is set, commands executed thanks to newverexec
or dlexecoptions will be echoed prior to execution. This option specifies a proxy to use for retrieving documents from FTP locations. It specifies either the complete URL or the server and port (as "server:port") of the proxy, and the proxy has to be a HTTP-based FTP proxy. This option takes precedence over config.proxy, if specified. If neither config.ftpproxynor config.proxyis set, the script uses the value the environment variables $ftp_proxy or $FTP_PROXY (in this order of precedence) are set to, or no FTP proxy at all. This option specifies a proxy to use for retrieving documents from HTTP locations. It specifies either the complete URL or the server and port (as "server:port") of the proxy. This option takes precedence over config.proxy, if specified. If neither config.httpproxynor config.proxyis set, the script uses the value the environment variables $http_proxy or $HTTP_PROXY (in this order of precedence) are set to, or no HTTP proxy at all. The date and time the script was last run updating the configuration file. This value is generated and updated automatically. - "newverexec
- A command to be executed whenever a new version of a program is found,
unless overridden on a per-program basis via prog.newverexec
. The command is executed under whatever shell the environment variable $SHELL defines. The command string is subject to expansion of the following placeholders (see " PLACEHOLDERS" for their meaning): "__NEWVER__", "__PROG__" , "__RAWVER__" , "__URL__" . Additionally, `~/' will be replaced by the user's home directory. - "nocache
- This option conserves some memory by not caching retrieved documents
(those fetched from prog.url
locations). By default, the script caches retrieved document so that program records referring to the same web page won't result in (unnecessary) multiple retrievals during the same session. - "plain
- This option causes the script to generate plain (as opposed to ANSI-enhanced)
output by default. The option may be overridden by specifying "--noplain"
on the command line. This option specifies a proxy to use for retrieving documents from both HTTP and FTP locations. It specifies either the complete URL or the server and port (as "server:port") of the proxy. The proxy set via this option may be overridden via config.ftpproxyand/or config.httpproxy. - "sortby
- This option specifies whether to sort prog
entries by program name ( progsection identifier) or URL when rewriting the configuration file. The default is to sort by name. - "xfersum
- Corresponds to the command line option "--xfersum"
. If set, the script will print a total of the amount of data that has been received at exit. Can be overridden via the command line switch "--noxfersum" . - "timeout
- The time (in seconds) after which attempted remote retrievals should be aborted. The default is 90 seconds.
- "verbose
- If this option is set, the script will also print version numbers that
haven't been obsoleted. The default is to print only new versions (and
error messages). This setting can be overridden via the command line
switch "--noverbose"
.
config = {
[...]
}
The keywords allowed inside ("[...]") the config
- Program sections each define for a single program (package, ...) an HTTP
or FTP URL based on which the latest version of that program available can
be determined by vcheck
- "comment
- An arbitrary comment string. If multiple such entries exist for a single program record, their relative order will be maintained when rewriting the configuration file.
- "deleteold
- This option defines whether the script should look for and delete any obsolete
versions of a program located in its download directory after each
?Usuccessful?N download of a new version of that program. A successful
download in this context is any download of a file of a known type whose
integrity could be verified. Overrides config.deleteold
; the deletion of obsolete versions is disabled by default and only activated by config.deleteoldor prog.deleteold. Any occurrence of prog.dlexplicitor prog.dlintermediatein a program's record inhibits application of deleteoldfor that program. Special note: Use at your own risk! - "disabled
- This option causes the program record in question to be ignored (except
when the command line switch "--force"
is used). - "dl
- This option specifies whether to download the program in question when
the script is run with the "--download"
option. By default, a program will be downloaded when a new version is found and the script is run with said parameter, unless config.dldefaultnois set. prog.dloverrides the latter option. - "dldir
- This option specifies a download directory on a per-program basis. If the
directory is absolute (i.e., relative to the root directory, as indicated
by a leading slash), it will be treated as an absolute path, otherwise it
will be considered relative to either config.dldir
, if specified, or the directory the script is executing in. - "dlexec
- Specifies a command to be executed after any successful download of the
program, overriding config.dlexec
(if set). A successful download in this context is one whose file type has been recognized and whose integrity could be confirmed. The command is executed under whatever shell the environment variable $SHELL is set to. The command string is subject to expansion of the following placeholders (see " PLACEHOLDERS" for their meaning): "__DLURL__", "__FILE__" , "__NEWVER__" , "__PROG__" , "__RAWVER__" , "__URL__" . Additionally, `~/' will be replaced by the user's home directory. - "dlexplicit
- Specifies an explicit download URL. Whenever a new version of the program in
question is found, the URL specified via this option will be downloaded (if
requested) instead of the one deduced from prog.url
and prog.regex. The command string is subject to expansion of the following placeholders (see " PLACEHOLDERS" for their meaning): "__NEWVER__", "__RAWVER__" . This option can also be used to, e.g., download multiple packages on detection of a new version, provided that their names can be specified. For an example of this, see " EXAMPLES". - "dlintermediate
- If this option is set, intermediate versions (i.e., version referenced at
url
newer than dlversionbut older than the most recent version available) will be downloaded as well if any are encountered when a new version of the program is found. This option is useful for downloading patches and suchlike, which depend on each other consecutively. The default is to ignore intermediate versions. - "dlprefs
- A semicolon- (`;'-) separated list of Perl-style regular expressions
defining download preferences. Each of the regular expressions is supposed
to match a particular file type that's possible or likely to be encountered.
The order in which the expressions occur defines their precedence (the first
matching expression will determine which of a set of available file types of a
given program version will be selected for download). This value overrides
default preferences possibly defined via config.dlprefs
. If neither config.dlprefsnor prog.dlprefsis set, the file to be downloaded is chosen pseudo-randomly, if multiple pattern matches occur. For these download preferences to make any sense, file- and version-matching expressions need to be sufficiently non-restrictive to match several possible extensions. For example, "foo-( "__VER__" )\\.t" will match both ".tar.gz" and ".tar.bz2" files, and setting `dlprefs' to "\\.tar\\.bz2$;\\.tar\\.gz$" will cause the script to preferrably download ".tar.bz2" files. - "dlreferrer
- Specifies an HTTP referrer to use when downloading a program package. By
default, the version-determining document (i.e., the last url
value, with placeholders expanded) is used. - "dlversion
- This parameter stores the last downloaded version of the program in question
and is updated whenever a new version is found (except when running in
read-only mode). If prog.transform
is set, the stored version will have been transformed from the one matched by prog.regex. - "errors
- This field stores the number of errors during version checks and is reset
once a check succeeds. A high value of this field is indicative of an
outdated URL or file name matching regular expression and will be remarked
upon by the script. Additionally, it is possible to limit the scope of
an operation to erroneous records via the "--errors"
command line parameter. This field stores the date and time the program in question was last checked (no matter whether successfully or unsuccessfully). - "newverexec
- A command to be executed whenever a new version of a program is found,
overriding a possible definition via config.newverexec
. The command is executed under whatever shell the environment variable $SHELL defines. The command string is subject to expansion of the following placeholders (see " PLACEHOLDERS" for their meaning): "__NEWVER__", "__PROG__" , "__RAWVER__" , "__URL__" . Additionally, `~/' will be replaced by the user's home directory. - "regex
- This required
field is supposed to contain a Perl-style regular expression matching desired versions of the program in question given the document at prog.urlas input. Note that the regexp needn't match the complete file name(--when considering a download, the script will auto-expand the match as seen fit. Regular expressions for matching programs' version numbers have to be written in such a way that the $1 part (see the "perlre" man page), if the entire expression matches, is exactly the version number. The option is subject to placeholder expansion: "__VER__" will be replaced by a pre-manufactured (non-greedy) regular expression matching version numbers compliant with any of a number of common schemes. Note that in order to yield a $1 match as required, "__VER__" still needs to be put in parentheses. For examples of prog.regexvalues, see " EXAMPLES". In order to cope with particularly complex remote scenarios (such as version-dependent directory hierarchies), multiple url, regex, and transformfields may be specified per program. In this case, the script will match urls and regexes starting with the first and continuously proceeding to the next field of each type (in sync, as long as both of them are available, or using the last one available otherwise) and match the regexp against the corresponding document. In order for this to be of any use, the second (and each potential later) urlwill have to contain a "__NEWVER__" or "__RAWVER__" placeholder (see " PLACEHOLDERS") which will be replaced by the previously matched latest [transformed] version (the same substitution is done for regex). The version that will finally be considered the latest for the program in question will be the one determined by matching the last regexagainst the last urls document. For an example of how this can be used in practice, see " EXAMPLES". Possible multiple transformfields will be processed in sync with the respective urland regexfields as long as additional transformfields are specified. If there are more urland/or regexfields than transformfields, the last-specified transformexpression will be used for further iterations. If, on the other hand, there are more transformthan url/ regexfields, further retrievals/matches will be done based on the last url/ regex. The author has, however, no idea how this could be of any use. When the config file is rewritten, multiple url, regex, and/or transformfields will be interleaved to facilitate comprehension and retain their relative order. - "tranform
- A Perl expression transforming a version number in $_
(obtained by a prog.regexmatch) in some way the user deems adequate. For examples of how this might come in handy, see " EXAMPLES". The return value of the code fragment, i.e., the value of its last expression, is used as the transformed version and will henceforth be the basis for version comparison for the program in question. - "urgency
- Defines the urgency with which to check for the specified program. Urgencies
allow for a crude selection of programs to check for via the "--urgency"
command line parameter. If there is no urgency defined, it defaults to either config.defaulturgency(if set) or medium. - "url
- This required
field defines the HTTP or FTP URL to retrieve as the document to scan for in order to detect the availability of new program versions by matching against prog.regex. Note that if the URL is a directory (especially, an FTP directory which is supposed to be listed), the URL needsto end in a slash (`/'). If the target document is an HTML page, its source code will be matched against prog.regex, aiming at links embedded in the document. An alternate download URL can be specified via prog.dlexplicit. In order to cope with particularly complex remote scenarios (such as version-dependent directory hierarchies), multiple url, regex, and transformfields may be specified per program. In this case, the script will match urls and regexes starting with the first and continuously proceeding to the next field of each type (in sync, as long as both of them are available, or using the last one available otherwise) and match the regexp against the corresponding document. In order for this to be of any use, the second (and each potential later) urlwill have to contain a "__NEWVER__" or "__RAWVER__" placeholder (see " PLACEHOLDERS") which will be replaced by the previously matched latest [transformed] version (the same substitution is done for regex). The version that will finally be considered the latest for the program in question will be the one determined by matching the last regexagainst the last urls document. For an example of how this can be used in practice, see " EXAMPLES". Possible multiple transformfields will be processed in sync with the respective urland regexfields as long as additional transformfields are specified. If there are more urland/or regexfields than transformfields, the last-specified transformexpression will be used for further iterations. If, on the other hand, there are more transformthan url/ regexfields, further retrievals/matches will be done based on the last url/ regex. The author has, however, no idea how this could be of any use. When the config file is rewritten, multiple url, regex, and/or transformfields will be interleaved and retain their relative order. - "version
- Stores the latest known version of the program. In contrast to
prog.dlversion
, this is the latest version detected, not the latest version downloaded. If a prog.transformoption is set, the stored version will have been transformed from the one matched by prog.regex.
prog Foo = {
[...]
}
The keywords allowed inside ("[...]") a prog
- In a number of string fields, certain placeholders are subject to
substitution by run-time values. These placeholders are (in alphabetical
order):
The (file) URL from which the latest version of the respective program was
downloaded.
The local path to the respective latest-version download.
"__NEWVER__"
- ""
- If you use Vim (version 5 or higher) as your editor, you can tell vcheck to
create a Vim syntax file providing syntax highlighting within the editor by
running the script as
vcheck --create-vim-syntax-file
If you wish to have Vim apply the syntax rules automatically when editing "~/.vcheck", add this line:
au BufEnter */.vcheck so $VIM/syntax/vcheck.vim
or, alternatively, one with an explicit path:
au BufEnter */.vcheck so /path/to/syntax/vcheck.vim
to your "~/.vimrc" and substitute an appropriate path. Of course you need to as well be sure to copy the file into the designated directory. - ""
- It's no problem to just check for new versions by default and run vcheck
again afterwards to download updated packages. Running the script as
vcheck -dc
or
vcheck --download --catch-up
respectively, will try to download only those files whose latest downloaded version has been knowingly obsoleted, without checking again for new versions of all other programs. - ""
- To check only those program locations that failed during the latest
attempt(s), run
vcheck -e
or
vcheck --errors
respectively. - ""
- If you add a line
dlretry = NUMBER
to your config file's configsection, vcheckwill retry to download a file up to NUMBER times if it detects that it was received incompletely. This will be the case if: - "-"
- the file has zero size
- "-"
- the downloaded file's extension was recognized, and a check by the respective decompressor etc. resulted in errors
- ""
- vcheck
caches data retrieved from URLs (unless nocacheis set in the config file), so if you specify exactly the same - ""
- If you're curious to know how many program records have actually been
accumulated in your config file over time, run vcheck
as
vcheck --syntax
This will check the config file's syntax and, as a side-effect, print the number of programs registered. - ""
- Even if you know from some other source that there is
a new version of a program vcheckis configured for, you can still use that to download the package. Just use its matching capabilities, e.g.:
vcheck -dm foo
- ""
- If one of your records points to patches of some program, and you want to
make sure you won't miss an intermediate one when downloading (and suppose
you don't run vcheck
in download mode too frequently), you can add the boolean field dlintermediateto the respective program's section in the config file, and vcheckwill try to download all versions newer than dlversion. Note that in those circumstances, dlversionis set to the latest (intermediate) version the download attempt succeeded for (which means that, if, say, versions 1 through 3 are to be downloaded and all downloads except that of version 1 succeed, dlversionwill nevertheless be set to 3). A useful example for this:
prog Linux/patches = {
dlintermediate
dlprefs = \.bz2$;\.gz$
dlversion = 2.3.6
regex = patch-(__VER__)\.[bg]z
url = ftp://ftp.kernel.org/pub/linux/kernel/v2.3/
version = 2.3.9
}
Supposing that 2.3.9 still is the latest version, running this in download mode will retrieve Linux kernel patches 2.3.7 through 2.3.9, *.bz2preferred to *.gz(but accepting the latter if the former is missing, rather than skipping the download entirely). - ""
- There may be complex remote site structures, involving version-dependent
directory hierarchies, such as the layout used by the server for the AC series
of Linux kernel patches. The principal layout of that site looks (or used to
look, anyway) like this:
...
.../linux-2.4/2.4.8/patch-2.4.8-ac1.gz
.../linux-2.4/2.4.8/patch-2.4.8-ac2.gz
...
.../linux-2.4/2.4.9/patch-2.4.9-ac1.gz
.../linux-2.4/2.4.9/patch-2.4.9-ac2.gz
...
The problem here is that the bottom-level directory's name varies depending on the regular Linux version an AC patch is based on. The way to deal with this most conveniently in vchecklooks like this:
prog Linux/patch/AC = {
dlintermediate
url = http://www.kernel.org/.../linux-2.4/
regex = (\d+\.\d+\.\d+)
url = http://www.kernel.org/.../linux-2.4/__NEWVER__/
regex = patch-(__VER__-ac\d+)\.gz
}
(Note that the URLs have been abbreviated for the sake of readability.) This kind of configuration will cause vcheckto start by retrieving the first urlfield's document and match the first regexagainst it. It will then proceed with the second urlfield's document, matching it against the second regex, replacing its __NEWVER__placeholder by the latest version previously matched. The version finally determined as the current version for the program record is the one determined by the last match. On a side note, version numbers determined during matches further back than the previous one can be accessed via delimiters of the format __NEWVER#__, where `#' is a number indicating the number (1..) of the url/ regexpair's version match it should be replaced by. For more details on the mechanism, see the descriptions of urland regexin " PROGRAM SECTIONS", and "PLACEHOLDERS". Regarding the example, it is left to the user to figure out how to extend the record to even automatically cope with changes to the Linux kernel's minor version. ":-)"Here's another example of a three-level hierarchy, which used to fit the GIMP's site layout at one point in time:
prog GIMP/devel/patch = {
comment = "Will download complete package if no patch available."
dlprefs = patch-.*?\.bz2$;patch-.*?\.gz$;gimp-.*?\.bz2$;gimp-.*?\.gz$
url = ftp://ftp.gimp.org/pub/gimp/
regex = (?<!\w)v(__VER__)
url = ftp://ftp.gimp.org/pub/gimp/v__NEWVER__/
regex = (?<!\w)v(__VER__)
url = ftp://ftp.gimp.org/pub/gimp/v__NEWVER1__/v__NEWVER__/
regex = (?:patch|gimp)-(__VER__)\.[bgt]
}
- ""
- If you want to retrieve some program whose version is, say, a date in format
"dd-mm-yyyy", this will be misinterpreted by the version comparator because
the most significant sub-"version" isn't the initial one. You can work around
this by specifying some Perl expression transforming the original version
in the respective program's section, such as:
transform = "s/(\d+)-(\d+)-(\d+)/$3-$2-$1/; $_"
This piece of code is given the respective version in $_, and after its evaluation, vcheckreplaces the original value by what the eval()returns. Alternatively, this would achieve the same:
transform = "join '-', reverse split /-/, $_"
- ""
- Some sites use redirection scripts for download URLs. Consider a situation
where a downloads page lists available packages of a program, with links
pointing to some server-side script referring your browser to some URL
which is in turn redirected by HTTP means
to a final file URL (the PHP site, for example, used to make use of this obscure scheme at one time). The way to cope with this in vcheckconsists in using a dlexplicitfield like this:
prog PHP = {
dlexplicit = http://www.php.net/distributions/php-__VER__.tar.gz
regex = php-(__VER__)\.t
url = http://www.php.net/downloads.php
}
Effectively, this will use the actual urlfield only to determine the current version and then paste it into a pattern of the corresponding download URL, thus bypassing the redirections. The obvious disadvantage of this feature consists in its increased dependency on server-side access structures. - ""
- Suppose you're interested in some program distributed via more than one
package (such as Vim, which is split into a source and a run-time package).
The means vcheck
provides to cope with this once again is the dlexplicitoption:
prog Vim = {
dlexplicit = ftp://ftp.vim.org/pub/editors/vim/unix/vim-__VER__-src.tar.gz
dlexplicit = ftp://ftp.vim.org/pub/editors/vim/unix/vim-__VER__-rt.tar.gz
regex = vim-(__VER__)(-src)?\.tar
url = ftp://ftp.vim.org/pub/editors/vim/unix/
}
- ""
- In order to have vcheck
keep track of what has been downloaded (and when), you might add something like this to your config file:
config = {
dlexec = "echo `date +%Y-%m-%d` '__PROG__' '__NEWVER__' >>~/.vchecklog"
}
Note however that program-specific dlexecwill take precedence over this setting. - ""
- With a little creativity, vcheck
can be used to check not only for latest versions of programs or packages, but also web site updates and the like. Also, the newverexec(see " GRAMMAR") field can be used to pass a link to an external download tool if for some reason vcheck's abilities prove insufficient for a particular scenario.
- Please make sure to read what's printed by vcheck
- ""
- for Foo
:
http://www.foo.org/pub/foo/foo-3.14.tar.gz
http://www.foo.org/pub/foo/foo-3.14.tar.bz2
http://www.foo.org/pub/foo/foo-3.14a.tar.gz
http://www.foo.org/pub/foo/foo-3.14alpha.tar.gz
http://www.foo.org/pub/foo/Foo-4.0.tar.gz
- ""
- for Bar
:
bar-0.01.zip
BAR-0.01.tar.bz2
- ""
- for Baz
:
http://www.baz.net/pub/download/baz-124.rpm
Now let's discuss what some specific calls to vcheck, each based on the above configuration, will result in. Again, for a complete list of command line options (all short options have an equivalent long one), see `vcheck --help` . This will check for all programs without updating the config file. It'll report Foo 3.14as new version (not 4.0, as regexdoesn't match this), as well as Baz 124. This will check for all programs, report as above and try to download the following file:
http://www.bar.org/bar/BAR-0.01.tar.bz2
Note that Baz 124isn't among, because there wasn't a link conforming to dlprefs, and downloads of Foohave been disabled explicitly. The errorsfield of Foois removed since the check succeeded. This will set dlversion= versionfor Barand Baz, without checking for the availability of new versions. Effectively, this will prevent future calls to vcheckwith parameter " "-d" " from downloading these files. This will step through all programs that downloads haven't been disabled for in principle and whose dlversionis lower than version(i.e., Barand Bazin our example). For these, vcheckwill requery the respective sites to determine a download URL, and try to download
http://www.bar.org/bar/BAR-0.01.tar.bz2
as in the above example. will check for new versions of Barand Baz. Note that you may have to quote the leading exclamation mark as well as some characters used in regular expressions specified on the command line, in order to prevent your shell from interpreting them. will check only for Bar, as it is the only program whose urgencyis at least mediumand whose name contains a `b'. will check only for Foo, since checking for that failed previously.
vcheck --help --grammar
as well as "GRAMMAR" before reading this section, to learn about command line parameters and the configuration file's grammar. Done so? Then read on...
Suppose there's a config file ~/.vcheck
config = {
dlprefs = \.tar\.bz2$;\.(tar\.|t)gz$;\.zip$
lastcheck = "1999-06-21 08:15"
}
prog Foo = {
dl = no
errors = 2
regex = foo-(__VER__)\.tar
urgency = high
url = http://www.foo.org/pub/foo/
}
prog Bar = {
dlversion = 0.01beta
regex = (?i:bar-(__VER__)\.tar)
url = http://www.bar.org/bar/index.html
version = 0.01
}
prog Baz = {
regex = baz-(\d+)\.tar
urgency = low
url = ftp://ftp.baz.net/pub/source/
version = 123
}
First of all, you can deduce from this what date and time vcheck
- ""
- First of all, vcheck
perfect, and it won't do in allkinds of situations. Yet I think it is able to cope with most of them, and if there's indeed some site which vcheckisn't able to determine download URLs from, or some version numbering scheme its heuristics choke on, you'll just have to deal with that manually. But for the majority of cases, vcheckshould facilitate keeping your setup up-to-date. - ""
- Don't run multiple instances in non-read-only mode with the same
configuration file, or else one will cause the changes made by the
others to get lost. vcheck
will prevent this situation from arising by employing a lock file, provided that your Perl setup supports it. Don't editthe config file while vcheckis running, either, or your changes will be overwritten when the script rewrites the file.
- ""
- vcheck
, the script itself - ""
- ~/.vcheck
, its configuration file In fact, vcheckdoesn't look for a config file ~/.vcheck, but for one of the same name as the script (with a possible extension stripped off). So if you rename the script to, say, foo.pland run it, it'll try to open ~/.foo. - ""
- ~/.vcheck.lock
, lock file created when not running in read-only mode Actually, the file's name is that of the config file with an extension of .lockadded.
- ""
- $http_proxy/$HTTP_PROXY and $ftp_proxy
/$FTP_PROXY, each in this order of precedence, specify the HTTP and/or (HTTP-based) FTP proxy to use, unless overridden. The format is either "server:port" or a complete URL. - ""
- $HOME, the current user's home directory
- ""
- $SHELL, used by Perl in unizoid environments when executing helper applications
- ""
- add option to config section allowing for the dlexec
entry to be "inherited" from the config section rather than be overridden by per-program dlexecs (also define order of execution!) - ""
- check behavior if an HTTP url
's download link references a different target base directory - ""
- make "--list" not rewrite the config file, thus allowing for it to be run in parallel to another instance
- ""
- add an option to re-download the latest version (if local file doesn't exist)?
- ""
- code clean-up: array used for download specifications -> hash
- ""
- determine and describe way of reliably matching directories consisting of but a version number on an FTP server independently of whether the page in question is received by proxy or without one
- ""
- scenario: link description contains version, download link entirely differently named
- ""
- separate "--force"
options for overriding disabled, dl? - ""
- max download size command line parameter?
- ""
- extend Vim syntax file generation to highlight placeholders in string variables' values?
- ""
- follow HTTP redirections
- ""
- evaluate HTTP headers after retrievals
- ""
- resume downloads?
- ""
- XMLize the config file format???
- ""
- make it multi-threaded???
- ""
- All output is currently printed on STDOUT.
- ""
- Placeholders are used but no way of escaping literal occurrences of those strings is provided.
- ""
- dlprefs
uses semicolons as delimiters, but there's no way of escaping them if they are meant as a part of one of the regular expressions. - ""
- There's presumably little to do in order to get vcheck
to run in Microsoft Windows. One issue worth noting is that directories (such as dldirvalues) are expecedted to use unizoid delimiters (i.e., slashes (`/'))--this should perhaps be revised to be portable.
- Mail bug reports to the author.
- vcheck