shell script null output

How do I redirect output and errors to /dev/null under bash / sh shell scri...

How do I redirect output and errors to /dev/null under bash / sh shell scripting? How do I redirect the output of stderr to stdout, and then redirect.

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the script will still crash. Because using > /dev/null 2>&1 will ...

the script will still crash. Because using > /dev/null 2>&1 will redirect all your command output (both stdout and stderr) to /dev/null, meaning no.

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There are two streams of output from a process that are generally sent to t...

There are two streams of output from a process that are generally sent to the terminal: standard output (which is bound to file descriptor 1), and.

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I believe what you are looking for is: ls good bad >/dev/null 2>&...

I believe what you are looking for is: ls good bad >/dev/null 2>&1. You have to redirect stdout first before duplicating it into stderr; if you.

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Therefore >/dev/null 2>&1 is redirect the output of your program ...

Therefore >/dev/null 2>&1 is redirect the output of your program to /dev/null. Much more information is available at The Linux Documentation.

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cat will list the contents of a file comming after cat to standard output a...

cat will list the contents of a file comming after cat to standard output and the > sends it to the file messages and wtmp where > means to first.

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I saw in Unix systems, especially while watching compilers do their work. T...

I saw in Unix systems, especially while watching compilers do their work. There are three standard sources of input and output for a program. see the command above is redirecting standard output into /dev/null, which from the command line by appending "2>>/var/log/logfile" to a shell command.

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jq '."$2"' will send literal."$2" as a expres...

jq '."$2"' will send literal."$2" as a expression for jq, what you want is: jq --arg key "$2" '.[$key]' "$1". Also removed useless use of cat. I don't.

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Redirection operators are evaluated left-to-right. what you did wrong was p...

Redirection operators are evaluated left-to-right. what you did wrong was put 2>&1 first, which points 2 to the same place as 1 currently is.

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The following sends standard output to the null device (bit bucket). . This...

The following sends standard output to the null device (bit bucket). . This example from The Linux Documentation Project is worth to mention.

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While not technically identical, from a pragmatic standpoint this will prov...

While not technically identical, from a pragmatic standpoint this will provide similar results to redirecting each command separately to /dev/null.

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First of all, note you are not using the variable correctly: if [ "pas...

First of all, note you are not using the variable correctly: if [ "pass_tc11"!= "" ]; then # ^ # missing $. Anyway, to check if a variable is empty or not.

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With Shell Script this is not different, and a quite common idiom, but not ...

With Shell Script this is not different, and a quite common idiom, but not so well understood, is the 2>&1, like in ls foo > /dev/null 2>&1. Here, for example, we are redirecting it to a file called dwn.220.v.ua: $ cat dwn.220.v.ua > dwn.220.v.ua

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Overview. In shell scripting, you often want to avoid printing error messag...

Overview. In shell scripting, you often want to avoid printing error messages to the console or discard any possible output the script could.

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Nothing will be shown because variable has no value i.e. NULL variable. Or ...

Nothing will be shown because variable has no value i.e. NULL variable. Or Use any text editor like vi to write the following shell script: . as 5 number is positive but for argument there is no output because our condition is not true(0) (no.

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