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bash_notes [2022/11/08 20:28] – [documentation links] rajubash_notes [2023/12/28 08:46] – [useful links] raju
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 ===== dummy ===== ===== dummy =====
 +==== other pages in this wiki ====
 +  * [[bash scripting]]
 +
 ==== useful links ==== ==== useful links ====
   * https://explainshell.com/ - useful for understanding complex shell commands   * https://explainshell.com/ - useful for understanding complex shell commands
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 ==== what is the difference between "ls > dirlist 2>&1" and "ls 2>&1 > dirlist"? ==== ==== what is the difference between "ls > dirlist 2>&1" and "ls 2>&1 > dirlist"? ====
 +The command
 +<code>
 +ls > dirlist 2>&1
 +</code>
 +directs both standard output (file descriptor 1) and standard error (file descriptor 2) to the file dirlist, while the command
 +<code>
 +ls 2>&1 > dirlist
 +</code>
 +directs only the standard output to file dirlist, because the standard error was made a copy of the standard output before the standard output was redirected to dirlist.
 +
 +To conclude, the order of redirections is significant.
 +
 +Ref:- https://www.gnu.org/software/bash/manual/html_node/Redirections.html -> 5th paragraph.
  
 ===== getopts ===== ===== getopts =====
bash_notes.txt · Last modified: 2023/12/28 08:49 by raju