03-15-2011
Quote:
Originally Posted by
omega666
and just to be clear again, when given 'w', the output of the string gets discarded or printed to stdout?
It depends on the caller's file descriptors and their flags.
Quote:
Originally Posted by popen opengroup documentation
The environment of the executed command shall be as if a child process were created within the
popen() call using the
fork() function, and the child invoked the
sh utility using the call:
execl(
shell path, "sh", "-c",
command, (char *)0) where
shell path is an unspecified pathname for the
sh utility.
So, as usual with fork/exec, the child will inherit all of its parents file descriptors that are not marked close-on-exec (FD_CLOEXEC). Additionally, there's the possibility of redirections in the command passed to "sh".
Regards,
Alister
Last edited by alister; 03-15-2011 at 05:52 AM..
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LEARN ABOUT DEBIAN
hxcopy
HXCOPY(1) HTML-XML-utils HXCOPY(1)
NAME
hxcopy - copy an HTML file and update its relative links
SYNOPSIS
hxcopy [ -i old-URL ] [ -o new-URL ] [ file-or-URL [ file-or-URL ] ]
DESCRIPTION
The hxcopy command copies its first argument to its second argument, while updating relative links. The input is assumed to be HTML or
XHTML and may be slightly reformatted in the process.
If the second argument is omitted, hxcopy writes to standard output. In this case the option -o is required. If the first argument is also
omitted, hxcopy reads from standard input. In this case the option -i is required.
OPTIONS
The following options are supported:
-i old-URL
For the purposes of updating relative links, act as if old-URL is the location from which the input is copied. If this option is
omitted, the actual location of the first argument is used for calculating relative links.
-o new-URL
For the purposed of updating relative links, act as if new-URL is the location to which the input is copied. If this option is
omitted, the actual location of the second argument is used for calculating relative links.
ENVIRONMENT
To use a proxy to retrieve remote files, set the environment variables http_proxy and ftp_proxy. E.g., http_proxy="http://localhost:8080/"
BUGS
Unlike the last argument of cp(1), the last argument of hxcopy must be a file, not a directory.
The second argument must be a local file. Writing to a URL is not yet implemented. To work around this, replace hxcopy file.html
http://example.org/file.html by hxcopy -o http://example.org/file.html file.html tmp.html and then upload tmp.html to the given URL with
some other command, such as curl(1). The first argument, however, may be a URL. hxcopy will download the given file. (Currently only HTTP
is supported.)
EXAMPLE
Assume the HTML file foo.html contains a relative link to "../bar.html". Here are some examples of commands:
hxcopy foo.html bar/foo.html
The file foo.html is copied to ../bar/foo.html and the relative link to "../bar.html" becomes "../../bar.html".
hxcopy foo.html ../foo.html
The file foo.html is copied to ../foo.html and the relative link to "../bar.html" is rewritten as "bar.html".
hxcopy -i http://my.org/dir1/foo.html -o http://my.org/foo.html file1.html file2.html
The file file1.html is copied to file2.html and the relative link to "../bar.html" is rewritten as "bar.html". A command like this
may be useful to update files that are later uploaded to a server.
SEE ALSO
cp(1), curl(1), hxwls(1)
6.x 9 Dec 2008 HXCOPY(1)