exec {} \;

ddaas · 02-05-2007, 08:29 AM

Hi there,
Could anyone explain me what are {} \; for at the end of the -exec ? What is exactly exec? Is is a shell command?

For example I could execute grep for any file which match a specific criteria. Something like this:
find / -type f -exec grep "something" {} \;

Thanks

colucix · 02-05-2007, 08:39 AM

The manual page of find explains this quite well: the string {} is replaced by the current file name being processed, that is all the files found by the find command are processed one by one and the {} construct tells to -exec which is the file to be processed now. All the argument after the -exec options are taken as the command to execute, until a literal ; is encountered. To pass literally a ; to -exec you have to escape it with a backslash in front of it, hence \;

pwc101 · 02-05-2007, 08:41 AM

The find man page explains this quite succinctly:

Code:

-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 encountered.  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.  The command  is  exe-
              cuted in the starting directory.

(Emphasis added) In essence, the {} means the file that's currently been found. Then \; (actually just a ;, but it needs to be escaped, hence the \) signifies the end of the command.

ddaas · 02-05-2007, 09:02 AM

Many thanks