run-parts(8) 實用程序的用途

至少在基於 Debian 的系統下，debianutilsrun-parts包中有一個實用程序，可用於各種腳本。例如在 /etc/X11/Xsession 中。它將執行在目錄中找到的所有執行檔。為什麼需要執行元件而可以與選項或實用程序一起使用？另外，什麼被認為是執行檔？看起來它不只是檢查文件權限：find``-perm``test``run-parts

# run-parts --list --lsbsysinit /etc/X11/Xsession.d | tail -1
/etc/X11/Xsession.d/90x11-common_ssh-agent
# ls -l /etc/X11/Xsession.d/90x11-common_ssh-agent
-rw-r--r-- 1 root root 629 2010-11-02 23:17 /etc/X11/Xsession.d/90x11-common_ssh-agent
# head /etc/X11/Xsession.d/90x11-common_ssh-agent
# $Id: 90x11-common_ssh-agent 305 2005-07-03 18:51:43Z dnusinow $

# This file is sourced by Xsession(5), not executed.

STARTSSH=
SSHAGENT=/usr/bin/ssh-agent
SSHAGENTARGS=

if has_option use-ssh-agent; then
 if [ -x "$SSHAGENT" ] && [ -z "$SSH_AUTH_SOCK" ] \
# 

您可以使用find代替run-parts，沒有辦法顯示哪個更好。但我認為 usingrun-parts更短（更少打字）並使您的腳本更易於維護。一個例子是/etc/crontab：

# /etc/crontab: system-wide crontab
# Unlike any other crontab you don't have to run the `crontab'
# command to install the new version when you edit this file
# and files in /etc/cron.d. These files also have username fields,
# that none of the other crontabs do.

SHELL=/bin/sh
PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin

# m h dom mon dow user  command
17 *    * * *   root    cd / && run-parts --report /etc/cron.hourly
25 6    * * *   root    test -x /usr/sbin/anacron || ( cd / && run-parts --report /etc/cron.daily )
47 6    * * 7   root    test -x /usr/sbin/anacron || ( cd / && run-parts --report /etc/cron.weekly )
52 6    1 * *   root    test -x /usr/sbin/anacron || ( cd / && run-parts --report /etc/cron.monthly )

debianutils對於第二個問題，您可以在原始碼中找到答案。在文件run-parts.c中，第 198 行：

/* Execute a file */                                                            
void run_part(char *progname)                                                   
{ 
    ....
    args[0] = progname;                                                         
    execv(progname, args);                                                      
    error("failed to exec %s: %s", progname, strerror(errno));                  
    exit(1);
    ....
}

你可以看到run-parts使用execv系統呼叫。因此，如果您的文件不是二進制執行檔或Interpreter script，execv則無法執行該文件。

筆記

• 什麼是Interpreter script：

從man execve, 部分Interpreter scripts:

Interpreter scripts
      An  interpreter  script  is  a  text  file  that has execute permission
      enabled and whose first line is of the form:

          #! interpreter [optional-arg]

      The interpreter must be a valid pathname for an executable which is not
      itself  a  script.   If  the filename argument of execve() specifies an
      interpreter script, then interpreter will be invoked with the following
      arguments:

          interpreter [optional-arg] filename arg...

      where arg...  is the series of words pointed to by the argv argument of
      execve().

      For portable use, optional-arg should either be absent, or be specified
      as  a  single word (i.e., it should not contain white space); see NOTES
      below.

• 您可以在此處查看 debianutils 原始碼。

引用自：https://unix.stackexchange.com/questions/121182