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(find.info)Multiple Files

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Multiple Files
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   Sometimes you need to process files alone.  But when you don't, it
is faster to run a command on as many files as possible at a time,
rather than once per file.  Doing this saves on the time it takes to
start up the command each time.

   To run a command on more than one file at once, use the `xargs'
command, which is invoked like this:

     xargs [OPTION...] [COMMAND [INITIAL-ARGUMENTS]]

   `xargs' reads arguments from the standard input, delimited by blanks
(which can be protected with double or single quotes or a backslash) or
newlines.  It executes the COMMAND (default is `/bin/echo') one or more
times with any INITIAL-ARGUMENTS followed by arguments read from
standard input.  Blank lines on the standard input are ignored.

   Instead of blank-delimited names, it is safer to use `find -print0'
or `find -fprint0' and process the output by giving the `-0' or
`--null' option to GNU `xargs', GNU `tar', GNU `cpio', or `perl'.

   You can use shell command substitution (backquotes) to process a
list of arguments, like this:

     grep -l sprintf `find $HOME -name '*.c' -print`

   However, that method produces an error if the length of the `.c'
file names exceeds the operating system's command-line length limit.
`xargs' avoids that problem by running the command as many times as
necessary without exceeding the limit:

     find $HOME -name '*.c' -print | xargs grep -l sprintf

   However, if the command needs to have its standard input be a
terminal (`less', for example), you have to use the shell command
substitution method.

Unsafe File Name Handling

Safe File Name Handling

Limiting Command Size

Interspersing File Names