From: "Stefan Bodewig" <[EMAIL PROTECTED]>: > On Fri, 21 Jun 2002, Kendall Collett <[EMAIL PROTECTED]> wrote: > > > This makes me suspect that the implementation of <apply> isn't doing > > the xargs thing where the system limits on number of command > > arguments etc. is taken into account. > > Err, right. > > > (Is there even a way to do this portably w/in Java?) > > If you can give me a pointer to "the xargs thing", I may be able to > answer the question 8-) > > Do you mean writing all command line arguments to a pipe with Unix's > xargs on the other end? I've never tried. Is it guaranteed to get > around the command line lenght issue?
Yes, xargs is guaranteed to avoid system limitations on command-line length and/or number of command line arguments. For example, where "grep getThing */*.java */*/*.java" can fail with something like "argument list too long" (E2BIG) if you have too many matching .java files, "find . -name '*.java' -print | xargs grep getThing" will not run into this problem because xargs will "spread" the argument list across multiple grep invocations to avoid running into any system limitations. (You can use the -t option to see the command invocations that xargs is making.) You can see another xargs example (for "rm" instead of "grep") at <http://www.bgw.org/tutorials/utilities/rm.php3>. > > If so, we could at least use it on Unix-like system - the whole <exec> > stuff is not portable anyway. Well, according to the documentation of E2BIG in the exec(2) manpage (I found a copy at <http://www.mcsr.olemiss.edu/cgi-bin/man-cgi?exec+2>), E2BIG can occur when "[t]he number of bytes in the new process's argument list is greater than the system-imposed limit {ARG_MAX} [see sysconf(2), intro(2), and limits.h]." I'm not sure if there is a way to get at the relevant numbers using (pure) Java. Kendall PS: Sorry for the tardy response--I was on vacation. -- To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]> For additional commands, e-mail: <mailto:[EMAIL PROTECTED]>
