Can anyone explain what are the uses of the exec command in shell scripting with simple examples?

What is the exec() function and its family? Why is this function used and how does its work? Please anyone explain these functions.

2018年9月5日 · The exec will replace the current process with the process resulting from executing its argument. In short, exec "$@" will run the command given by the command line parameters in such a way that the current process is replaced by it (if the exec is able to execute the command at all).

2013年6月28日 · I have a list of certain files that I see using the command below, but how can I copy those files listed into another folder, say ~/test? find . -mtime 1 -exec du -hc {} +

2018年6月6日 · Each -exec also acts like a "test" on the pathnames found by find, just like -type and -name does. If the command returns a zero exit status (signifying "success"), the next part of the find command is considered, otherwise the find command continues with the next pathname.

2015年4月10日 · As per man find: -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 command lines. Only one ...

2014年10月13日 · Not quite a duplicate of Which is faster, 'find -exec' or 'find | xargs -0'? since this asks about the differences and that question asks about which is faster, but the difference is that xargs invokes the command in batches while find -exec invokes the command once per result, which makes xargs faster.

2023年10月31日 · I'd like to find the files in the current directory that contain the text "chrome". $ find . -exec grep chrome find: missing argument to `-exec' What am I doing wrong?

2009年8月1日 · Technically speaking it duplicates, or copies, stderr onto stdout. Usually you don't need the exec to perform this. A more typical use of exec with file descriptors is to indicate that you want to assign a file to an unused file descriptor, e.g. exec 35< my_input BTW Don't forget that the sequence of declaration when piping to a file is …

A -exec command must be terminated with a ; (so you usually need to type \; or ';' to avoid interpretion by the shell) or a +. The difference is that with ;, the command is called once per file, with +, it is called just as few times as possible (usually once, but there is a maximum length for a command line, so it might be split up) with all filenames. See this example: $ cat /tmp/echoargs ...