如何在xargs命令中使用＆>>？

Question

Experts,

Following this question I execute this command:

xargs argument using posix:

find <somePath> -name '*.html' | sort -n | xargs -I{} sh -c 'w3m "{}" &>> "test.log"' --{}

I get the following errors:

• file.hml: -c: line 0: syntax error near unexpected token `>'
• file.hml: -c: line 0: `w3m ".html" &>> "test.log"'

Why does bash not understand &>> in my line execution?

As @Nahuel Fouilleul said "sh (posix) doesn't recognize the (bash) redirection &>>".

xargs argument using bash

However the solution proposed is not working when I execute the following command:

find <somePath> -name '*.html' | sort -n | xargs -I{} w3m {} &>> "test.log"

I receive this error:

• bash: syntax error near unexpected token `>'

Why does bash not understand &>> in my line execution? See my answer

Answer 1

it may not work if sh (posix) doesn't recognize the (bash) redirection &>> . but the command still can break for certain file names.

Command should be.

.. | xargs -I{} bash -c 'w3m "$1" &>> "test.log"' "process_name_you_want" {}

or to avoid to open log file for each file redirection can be moved out

.. | xargs -I{} w3m {} &>> "test.log"

EDIT: answer is general to a tool which processes files and write to output, after looking at w3m tool it seems it's a web browser in a console, what are you trying to do ?

Answer 2

From here I realized that the operator "&>>" is only available from Bash version 4 . I am using Bash version 3.2.51 so it doesn't work.

For versions previous to bash 4 two operators are needed:

w3m >> test.log 2>&1

where:

">>" append stdout to test.log

"2>&1" redirect the stderr to where the sdout is going

So the command working with xargs is the following:

.. | xargs -I{} w3m {} >> "test.log" 2>&1