3
I want to execute a command on the paths found with the find
command and I want to use +
to reduce the number of times the external command is launched.
Critically, the command has a fixed value final argument. Here's a concrete example with echo
as the command, although in the real :
mkdir blah && cd blah
touch fooA
touch fooB
find . -name 'foo*' -exec echo {} second +
I would expect this to print:
./fooA ./fooB second
but instead I get the error find: missing argument to
-exec'. I've tried all sorts of permutations to get it to work with +. Why isn't this working? It works find with the
\;` variant:
find . -name 'foo*' -exec echo {} second \;
./fooB second
./fooA second
... but that's not what I'm after.
find --version
reports:
find (GNU findutils) 4.4.2
Copyright (C) 2007 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
Written by Eric B. Decker, James Youngman, and Kevin Dalley.
Built using GNU gnulib version e5573b1bad88bfabcda181b9e0125fb0c52b7d3b
Features enabled: D_TYPE O_NOFOLLOW(enabled) LEAF_OPTIMISATION FTS() CBO(level=0)
Here's an excerpt from the man pages covering the +
and ;
forms:
-exec command ;
Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encoun‐
tered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is
alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the
EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting direc‐
tory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead.
-exec command {} +
This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the
total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its com‐
mand lines. Only one instance of `{}' is allowed within the command. The command is executed in the starting directory.
What shell are you using? – roaima – 2015-03-16T23:59:01.553
According to the man page the
-exec
command expects the{}
at the very end of the expression since it tries to concatenate the files found. Putting thesecond
before the{}
will work but, of course, that does not really help you. The error message is a little misleading. – Marcus Rickert – 2015-03-17T00:02:04.133Where in the man do you see that? I included the man output on my system in question. For the
\;
form it is clear that multiple{}
are allowed, implying they don't have to be at the end of the command. The+
form saysthe command line is built by appending each selected file name at the end
- but I read "the end" here as the end of the string which will ultimately be used to replace the{}
. If it was always at the end, why use {}? The textOnly one instance of
{}' is allowed within the command` imlies that one instance can be anywhere (or else why not restrict it)? – BeeOnRope – 2015-03-18T23:48:55.853