Bash script using output of mount as a variable throws numerous errors

up vote
3
down vote

favorite

Ubuntu 18.04 server + LXDE. I can't get the hang of this bash scripting.

This is my script "start" (with line numbering):

#!/bin/bash
reply=sudo mount 192.168.0.2:/home/dk/NFS /home/dk/NFS
if $reply == 0
then 
 echo "NFS mounted OK"
else 
 echo "Mounting NFS failed: $reply"
fi

reply=sudo mount LABEL="60GB" /home/dk/60GB
if $reply == 0
then 
 echo "60GB mounted OK"
else 
 echo "Mounting 60GB failed: $reply"
fi
exit 0

This is the result of running it:

$ ./scripts/start
mount: only root can do that
./start: line 3: ==: command not found
Mounting NFS failed: 
mount: only root can do that
./start: line 11: ==: command not found
Mounting 60GB failed: 
$

Why did it ignore the sudo before mount?

Why did it not consider if to be a command ?

Why did it not print the (non-zero) value of $reply?

edited 12 mins ago

Zanna

48.6k13120230

asked 9 hours ago

Dave Kimble

192

add a commentÂ |Â

up vote
3
down vote

favorite

Ubuntu 18.04 server + LXDE. I can't get the hang of this bash scripting.

This is my script "start" (with line numbering):

#!/bin/bash
reply=sudo mount 192.168.0.2:/home/dk/NFS /home/dk/NFS
if $reply == 0
then 
 echo "NFS mounted OK"
else 
 echo "Mounting NFS failed: $reply"
fi

reply=sudo mount LABEL="60GB" /home/dk/60GB
if $reply == 0
then 
 echo "60GB mounted OK"
else 
 echo "Mounting 60GB failed: $reply"
fi
exit 0

This is the result of running it:

$ ./scripts/start
mount: only root can do that
./start: line 3: ==: command not found
Mounting NFS failed: 
mount: only root can do that
./start: line 11: ==: command not found
Mounting 60GB failed: 
$

Why did it ignore the sudo before mount?

Why did it not consider if to be a command ?

Why did it not print the (non-zero) value of $reply?

edited 12 mins ago

Zanna

48.6k13120230

asked 9 hours ago

Dave Kimble

192

add a commentÂ |Â

up vote
3
down vote

favorite

Ubuntu 18.04 server + LXDE. I can't get the hang of this bash scripting.

This is my script "start" (with line numbering):

#!/bin/bash
reply=sudo mount 192.168.0.2:/home/dk/NFS /home/dk/NFS
if $reply == 0
then 
 echo "NFS mounted OK"
else 
 echo "Mounting NFS failed: $reply"
fi

reply=sudo mount LABEL="60GB" /home/dk/60GB
if $reply == 0
then 
 echo "60GB mounted OK"
else 
 echo "Mounting 60GB failed: $reply"
fi
exit 0

This is the result of running it:

$ ./scripts/start
mount: only root can do that
./start: line 3: ==: command not found
Mounting NFS failed: 
mount: only root can do that
./start: line 11: ==: command not found
Mounting 60GB failed: 
$

Why did it ignore the sudo before mount?

Why did it not consider if to be a command ?

Why did it not print the (non-zero) value of $reply?

edited 12 mins ago

Zanna

48.6k13120230

asked 9 hours ago

Dave Kimble

192

Ubuntu 18.04 server + LXDE. I can't get the hang of this bash scripting.

This is my script "start" (with line numbering):

#!/bin/bash
reply=sudo mount 192.168.0.2:/home/dk/NFS /home/dk/NFS
if $reply == 0
then 
 echo "NFS mounted OK"
else 
 echo "Mounting NFS failed: $reply"
fi

reply=sudo mount LABEL="60GB" /home/dk/60GB
if $reply == 0
then 
 echo "60GB mounted OK"
else 
 echo "Mounting 60GB failed: $reply"
fi
exit 0

This is the result of running it:

$ ./scripts/start
mount: only root can do that
./start: line 3: ==: command not found
Mounting NFS failed: 
mount: only root can do that
./start: line 11: ==: command not found
Mounting 60GB failed: 
$

Why did it ignore the sudo before mount?

Why did it not consider if to be a command ?

Why did it not print the (non-zero) value of $reply?

command-line bash scripts

edited 12 mins ago

Zanna

48.6k13120230

asked 9 hours ago

Dave Kimble

192

edited 12 mins ago

Zanna

48.6k13120230

asked 9 hours ago

Dave Kimble

192

edited 12 mins ago

Zanna

48.6k13120230

edited 12 mins ago

Zanna

48.6k13120230

edited 12 mins ago

Zanna

48.6k13120230

asked 9 hours ago

Dave Kimble

192

asked 9 hours ago

Dave Kimble

192

asked 9 hours ago

Dave Kimble

192

add a commentÂ |Â

3 Answers
3

active

oldest

votes

up vote
7
down vote

Well you're assigning output of a command incorrectly. Should be:

reply=$(sudo mount 192.168.0.2:/home/dk/NFS /home/dk/NFS)

That's called command substitution. Sometimes you see it in old Bourne shell syntax with backquotes instead of $(...), but that's not recommended nowadays because backquotes can't be nested easily, while you can do nested $( cmd1 $(cmd2))

Why did it not consider "if" to be a command?

If statements operate on commands, but what you give is variable $reply, which only exists temporarily ( see later in the answer about that) so it exists only for mount command's environment, but the shell running the script knows nothing of it - it doesn't exist. To compare strings use [, and yes it's a command also known as test. So do

if test "$reply" == 0

See quotes? That's important, otherwise if there's spaces, shell will expand variable to two or more separate entities not one.

But if you want to check exit status of command, just do

if mount 192.168.0.2:/home/dk/NFS /home/dk/NFS

See no sudo? That's because it's usually redundant to use sudo in script multiple times. Just call script itself with sudo and all commands will have root privilege.

I'd also say echo is redundant because mount command already can print errors to terminal, but if you want custom message, you can do

if mount 192.168.0.2:/home/dk/NFS /home/dk/NFS 1> /dev/null
then
 echo "Success"
else
 echo "Fail"
fi

Because of 1> normal output is suppressed (actually redirected to /dev/null especially for that purpose) but errors will show if anything goes wrong.

Why did it ignore the "sudo" before "mount" ?

As for why you're getting error message that's because the form

reply=sudo mount 192.168.0.2:/home/dk/NFS /home/dk/NFS

is treated as envvariable=value command arg1 arg2, i.e. you're putting variable result with value sudo into environment of mount command. The command will know about it, but after command exits - the variable is gone too.

Why did it not print the (non-zero) value of $reply?

Because reply doesn't store exit status as explained before. There's actually a variable for that provided by shell already, $? so use that as

if [ $? -eq 0 ]

Rinse and repeat the suggestions for other statements in your script.

Good luck

edited 9 hours ago

muru

132k19280478

answered 9 hours ago

Sergiy Kolodyazhnyy

67k9135297

Thanks, working now. What a horrible syntax
â€“Â Dave Kimble
8 hours ago

1

@DaveKimble Yeah, it takes time getting used to the syntax in shell scripting. But eventually you'll get it with enough practice and reading answers here and on unix.stackexchange.com or stackoverflow. And you can always try Python. Syntax is nicer there and faster but you have to call external commands like mount via Popen module. Btw, if the answer solved the problem, don't forget to mark it as accepted ( grey checkmark ). Or leave it unmarked. It's not a requirement.
â€“Â Sergiy Kolodyazhnyy
8 hours ago

add a commentÂ |Â

up vote
0
down vote

Problems with your script:

You missed ` for sudo mount .. command. To execute a command, you need to put it back quotes `command` or $(command). You can capture return value of the script using $? as well.

If loop construct was wrong

if [ $var -eq/-lt/-gt "string"/number ]
then
echo "...."
else
echo "..."
fi; <=== Most users miss this.

** Edited script**

#!/bin/bash

reply=`sudo mount 192.168.0.2:/home/dk/NFS /home/dk/NFS`

if [ $reply -eq "0" ]
then 
echo "NFS mounted OK"
else 
echo "Mounting NFS failed: $reply"
fi;

reply=`sudo mount LABEL="60GB" /home/dk/60GB`
if[ $reply -eq "0" ]
then 
 echo "60GB mounted OK"
else 
 echo "Mounting 60GB failed: $reply"
fi;
exit 0

edited 6 hours ago

muru

132k19280478

answered 6 hours ago

user3409057

Most users miss what? The semicolon after fi is definitely not needed. And command substitution has been mentioned by Sergiy already. Note that $(command) should be preferred to backticks.
â€“Â Melebius
5 hours ago

add a commentÂ |Â

up vote
0
down vote

In addition to Sergiy's good answer, you could consider using AND and OR lists to quickly check if a command returns an exit status of zero (succeeded) or not, for example

command && echo "command succeeded" || echo "command failed"

Here's an excerpt from man bash:

AND and OR lists are sequences of one or more pipelines separated by
the && and || control operators, respectively. AND and OR lists are
executed with left associativity. An AND list has the form
 command1 && command2
command2 is executed if, and only if, command1 returns an exit status
of zero.

An OR list has the form
 command1 || command2
command2 is executed if and only if command1 returns a non-zero exit
status. The return status of AND and OR lists is the exit status of
the last command executed in the list.

You could combine them, and also see the exit status if you want, with your example like:

sudo mount 192.168.0.2:/home/dk/NFS /home/dk/NFS && 
echo "NFS mounted OK" || echo "Mounting NFS failed: $?"

answered 18 mins ago

Xen2050

6,46912142

add a commentÂ |Â

Your Answer

StackExchange.ready(function()
var channelOptions =
tags: "".split(" "),
id: "89"
;
initTagRenderer("".split(" "), "".split(" "), channelOptions);

StackExchange.using("externalEditor", function()
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled)
StackExchange.using("snippets", function()
createEditor();
);

else
createEditor();

);

function createEditor()
StackExchange.prepareEditor(
heartbeatType: 'answer',
convertImagesToLinks: true,
noModals: false,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader:
brandingHtml: "",
contentPolicyHtml: "",
allowUrls: true
,
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
);

);

draft saved

draft discarded

StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2faskubuntu.com%2fquestions%2f1088748%2fbash-script-using-output-of-mount-as-a-variable-throws-numerous-errors%23new-answer', 'question_page');

);

Post as a guest

Name

3 Answers
3

active

oldest

votes

3 Answers
3

active

oldest

votes

up vote
7
down vote

Well you're assigning output of a command incorrectly. Should be:

reply=$(sudo mount 192.168.0.2:/home/dk/NFS /home/dk/NFS)

Why did it not consider "if" to be a command?

if test "$reply" == 0

See quotes? That's important, otherwise if there's spaces, shell will expand variable to two or more separate entities not one.

But if you want to check exit status of command, just do

if mount 192.168.0.2:/home/dk/NFS /home/dk/NFS

See no sudo? That's because it's usually redundant to use sudo in script multiple times. Just call script itself with sudo and all commands will have root privilege.

I'd also say echo is redundant because mount command already can print errors to terminal, but if you want custom message, you can do

if mount 192.168.0.2:/home/dk/NFS /home/dk/NFS 1> /dev/null
then
 echo "Success"
else
 echo "Fail"
fi

Because of 1> normal output is suppressed (actually redirected to /dev/null especially for that purpose) but errors will show if anything goes wrong.

Why did it ignore the "sudo" before "mount" ?

As for why you're getting error message that's because the form

reply=sudo mount 192.168.0.2:/home/dk/NFS /home/dk/NFS

Why did it not print the (non-zero) value of $reply?

Because reply doesn't store exit status as explained before. There's actually a variable for that provided by shell already, $? so use that as

if [ $? -eq 0 ]

Rinse and repeat the suggestions for other statements in your script.

Good luck

edited 9 hours ago

muru

132k19280478

answered 9 hours ago

Sergiy Kolodyazhnyy

67k9135297

Thanks, working now. What a horrible syntax
â€“Â Dave Kimble
8 hours ago

1

@DaveKimble Yeah, it takes time getting used to the syntax in shell scripting. But eventually you'll get it with enough practice and reading answers here and on unix.stackexchange.com or stackoverflow. And you can always try Python. Syntax is nicer there and faster but you have to call external commands like mount via Popen module. Btw, if the answer solved the problem, don't forget to mark it as accepted ( grey checkmark ). Or leave it unmarked. It's not a requirement.
â€“Â Sergiy Kolodyazhnyy
8 hours ago

add a commentÂ |Â

up vote
7
down vote

Well you're assigning output of a command incorrectly. Should be:

reply=$(sudo mount 192.168.0.2:/home/dk/NFS /home/dk/NFS)

Why did it not consider "if" to be a command?

if test "$reply" == 0

See quotes? That's important, otherwise if there's spaces, shell will expand variable to two or more separate entities not one.

But if you want to check exit status of command, just do

if mount 192.168.0.2:/home/dk/NFS /home/dk/NFS

See no sudo? That's because it's usually redundant to use sudo in script multiple times. Just call script itself with sudo and all commands will have root privilege.

I'd also say echo is redundant because mount command already can print errors to terminal, but if you want custom message, you can do

if mount 192.168.0.2:/home/dk/NFS /home/dk/NFS 1> /dev/null
then
 echo "Success"
else
 echo "Fail"
fi

Because of 1> normal output is suppressed (actually redirected to /dev/null especially for that purpose) but errors will show if anything goes wrong.

Why did it ignore the "sudo" before "mount" ?

As for why you're getting error message that's because the form

reply=sudo mount 192.168.0.2:/home/dk/NFS /home/dk/NFS

Why did it not print the (non-zero) value of $reply?

Because reply doesn't store exit status as explained before. There's actually a variable for that provided by shell already, $? so use that as

if [ $? -eq 0 ]

Rinse and repeat the suggestions for other statements in your script.

Good luck

edited 9 hours ago

muru

132k19280478

answered 9 hours ago

Sergiy Kolodyazhnyy

67k9135297

Thanks, working now. What a horrible syntax
â€“Â Dave Kimble
8 hours ago

1

@DaveKimble Yeah, it takes time getting used to the syntax in shell scripting. But eventually you'll get it with enough practice and reading answers here and on unix.stackexchange.com or stackoverflow. And you can always try Python. Syntax is nicer there and faster but you have to call external commands like mount via Popen module. Btw, if the answer solved the problem, don't forget to mark it as accepted ( grey checkmark ). Or leave it unmarked. It's not a requirement.
â€“Â Sergiy Kolodyazhnyy
8 hours ago

add a commentÂ |Â

up vote
7
down vote

Well you're assigning output of a command incorrectly. Should be:

reply=$(sudo mount 192.168.0.2:/home/dk/NFS /home/dk/NFS)

Why did it not consider "if" to be a command?

if test "$reply" == 0

See quotes? That's important, otherwise if there's spaces, shell will expand variable to two or more separate entities not one.

But if you want to check exit status of command, just do

if mount 192.168.0.2:/home/dk/NFS /home/dk/NFS

See no sudo? That's because it's usually redundant to use sudo in script multiple times. Just call script itself with sudo and all commands will have root privilege.

I'd also say echo is redundant because mount command already can print errors to terminal, but if you want custom message, you can do

if mount 192.168.0.2:/home/dk/NFS /home/dk/NFS 1> /dev/null
then
 echo "Success"
else
 echo "Fail"
fi

Because of 1> normal output is suppressed (actually redirected to /dev/null especially for that purpose) but errors will show if anything goes wrong.

Why did it ignore the "sudo" before "mount" ?

As for why you're getting error message that's because the form

reply=sudo mount 192.168.0.2:/home/dk/NFS /home/dk/NFS

Why did it not print the (non-zero) value of $reply?

Because reply doesn't store exit status as explained before. There's actually a variable for that provided by shell already, $? so use that as

if [ $? -eq 0 ]

Rinse and repeat the suggestions for other statements in your script.

Good luck

edited 9 hours ago

muru

132k19280478

answered 9 hours ago

Sergiy Kolodyazhnyy

67k9135297

Well you're assigning output of a command incorrectly. Should be:

reply=$(sudo mount 192.168.0.2:/home/dk/NFS /home/dk/NFS)

Why did it not consider "if" to be a command?

if test "$reply" == 0

See quotes? That's important, otherwise if there's spaces, shell will expand variable to two or more separate entities not one.

But if you want to check exit status of command, just do

if mount 192.168.0.2:/home/dk/NFS /home/dk/NFS

See no sudo? That's because it's usually redundant to use sudo in script multiple times. Just call script itself with sudo and all commands will have root privilege.

I'd also say echo is redundant because mount command already can print errors to terminal, but if you want custom message, you can do

if mount 192.168.0.2:/home/dk/NFS /home/dk/NFS 1> /dev/null
then
 echo "Success"
else
 echo "Fail"
fi

Because of 1> normal output is suppressed (actually redirected to /dev/null especially for that purpose) but errors will show if anything goes wrong.

Why did it ignore the "sudo" before "mount" ?

As for why you're getting error message that's because the form

reply=sudo mount 192.168.0.2:/home/dk/NFS /home/dk/NFS

Why did it not print the (non-zero) value of $reply?

Because reply doesn't store exit status as explained before. There's actually a variable for that provided by shell already, $? so use that as

if [ $? -eq 0 ]

Rinse and repeat the suggestions for other statements in your script.

Good luck

edited 9 hours ago

muru

132k19280478

answered 9 hours ago

Sergiy Kolodyazhnyy

67k9135297

edited 9 hours ago

muru

132k19280478

edited 9 hours ago

muru

132k19280478

edited 9 hours ago

muru

132k19280478

answered 9 hours ago

Sergiy Kolodyazhnyy

67k9135297

answered 9 hours ago

Sergiy Kolodyazhnyy

67k9135297

answered 9 hours ago

Sergiy Kolodyazhnyy

67k9135297

Thanks, working now. What a horrible syntax
â€“Â Dave Kimble
8 hours ago

1

@DaveKimble Yeah, it takes time getting used to the syntax in shell scripting. But eventually you'll get it with enough practice and reading answers here and on unix.stackexchange.com or stackoverflow. And you can always try Python. Syntax is nicer there and faster but you have to call external commands like mount via Popen module. Btw, if the answer solved the problem, don't forget to mark it as accepted ( grey checkmark ). Or leave it unmarked. It's not a requirement.
â€“Â Sergiy Kolodyazhnyy
8 hours ago

add a commentÂ |Â

Thanks, working now. What a horrible syntax
â€“Â Dave Kimble
8 hours ago

1

@DaveKimble Yeah, it takes time getting used to the syntax in shell scripting. But eventually you'll get it with enough practice and reading answers here and on unix.stackexchange.com or stackoverflow. And you can always try Python. Syntax is nicer there and faster but you have to call external commands like mount via Popen module. Btw, if the answer solved the problem, don't forget to mark it as accepted ( grey checkmark ). Or leave it unmarked. It's not a requirement.
â€“Â Sergiy Kolodyazhnyy
8 hours ago

Thanks, working now. What a horrible syntax
â€“Â Dave Kimble
8 hours ago

@DaveKimble Yeah, it takes time getting used to the syntax in shell scripting. But eventually you'll get it with enough practice and reading answers here and on unix.stackexchange.com or stackoverflow. And you can always try Python. Syntax is nicer there and faster but you have to call external commands like mount via Popen module. Btw, if the answer solved the problem, don't forget to mark it as accepted ( grey checkmark ). Or leave it unmarked. It's not a requirement.
â€“Â Sergiy Kolodyazhnyy
8 hours ago

add a commentÂ |Â

up vote
0
down vote

Problems with your script:

You missed ` for sudo mount .. command. To execute a command, you need to put it back quotes `command` or $(command). You can capture return value of the script using $? as well.

If loop construct was wrong

if [ $var -eq/-lt/-gt "string"/number ]
then
echo "...."
else
echo "..."
fi; <=== Most users miss this.

** Edited script**

#!/bin/bash

reply=`sudo mount 192.168.0.2:/home/dk/NFS /home/dk/NFS`

if [ $reply -eq "0" ]
then 
echo "NFS mounted OK"
else 
echo "Mounting NFS failed: $reply"
fi;

reply=`sudo mount LABEL="60GB" /home/dk/60GB`
if[ $reply -eq "0" ]
then 
 echo "60GB mounted OK"
else 
 echo "Mounting 60GB failed: $reply"
fi;
exit 0

edited 6 hours ago

muru

132k19280478

answered 6 hours ago

user3409057

Most users miss what? The semicolon after fi is definitely not needed. And command substitution has been mentioned by Sergiy already. Note that $(command) should be preferred to backticks.
â€“Â Melebius
5 hours ago

add a commentÂ |Â

up vote
0
down vote

Problems with your script:

You missed ` for sudo mount .. command. To execute a command, you need to put it back quotes `command` or $(command). You can capture return value of the script using $? as well.

If loop construct was wrong

if [ $var -eq/-lt/-gt "string"/number ]
then
echo "...."
else
echo "..."
fi; <=== Most users miss this.

** Edited script**

#!/bin/bash

reply=`sudo mount 192.168.0.2:/home/dk/NFS /home/dk/NFS`

if [ $reply -eq "0" ]
then 
echo "NFS mounted OK"
else 
echo "Mounting NFS failed: $reply"
fi;

reply=`sudo mount LABEL="60GB" /home/dk/60GB`
if[ $reply -eq "0" ]
then 
 echo "60GB mounted OK"
else 
 echo "Mounting 60GB failed: $reply"
fi;
exit 0

edited 6 hours ago

muru

132k19280478

answered 6 hours ago

user3409057

Most users miss what? The semicolon after fi is definitely not needed. And command substitution has been mentioned by Sergiy already. Note that $(command) should be preferred to backticks.
â€“Â Melebius
5 hours ago

add a commentÂ |Â

up vote
0
down vote

Problems with your script:

You missed ` for sudo mount .. command. To execute a command, you need to put it back quotes `command` or $(command). You can capture return value of the script using $? as well.

If loop construct was wrong

if [ $var -eq/-lt/-gt "string"/number ]
then
echo "...."
else
echo "..."
fi; <=== Most users miss this.

** Edited script**

#!/bin/bash

reply=`sudo mount 192.168.0.2:/home/dk/NFS /home/dk/NFS`

if [ $reply -eq "0" ]
then 
echo "NFS mounted OK"
else 
echo "Mounting NFS failed: $reply"
fi;

reply=`sudo mount LABEL="60GB" /home/dk/60GB`
if[ $reply -eq "0" ]
then 
 echo "60GB mounted OK"
else 
 echo "Mounting 60GB failed: $reply"
fi;
exit 0

edited 6 hours ago

muru

132k19280478

answered 6 hours ago

user3409057

Problems with your script:

You missed ` for sudo mount .. command. To execute a command, you need to put it back quotes `command` or $(command). You can capture return value of the script using $? as well.

If loop construct was wrong

if [ $var -eq/-lt/-gt "string"/number ]
then
echo "...."
else
echo "..."
fi; <=== Most users miss this.

** Edited script**

#!/bin/bash

reply=`sudo mount 192.168.0.2:/home/dk/NFS /home/dk/NFS`

if [ $reply -eq "0" ]
then 
echo "NFS mounted OK"
else 
echo "Mounting NFS failed: $reply"
fi;

reply=`sudo mount LABEL="60GB" /home/dk/60GB`
if[ $reply -eq "0" ]
then 
 echo "60GB mounted OK"
else 
 echo "Mounting 60GB failed: $reply"
fi;
exit 0

edited 6 hours ago

muru

132k19280478

answered 6 hours ago

user3409057

edited 6 hours ago

muru

132k19280478

edited 6 hours ago

muru

132k19280478

edited 6 hours ago

muru

132k19280478

answered 6 hours ago

user3409057

answered 6 hours ago

user3409057

answered 6 hours ago

user3409057

Most users miss what? The semicolon after fi is definitely not needed. And command substitution has been mentioned by Sergiy already. Note that $(command) should be preferred to backticks.
â€“Â Melebius
5 hours ago

add a commentÂ |Â

Most users miss what? The semicolon after fi is definitely not needed. And command substitution has been mentioned by Sergiy already. Note that $(command) should be preferred to backticks.
â€“Â Melebius
5 hours ago

Most users miss what? The semicolon after fi is definitely not needed. And command substitution has been mentioned by Sergiy already. Note that $(command) should be preferred to backticks.
â€“Â Melebius
5 hours ago

add a commentÂ |Â

up vote
0
down vote

In addition to Sergiy's good answer, you could consider using AND and OR lists to quickly check if a command returns an exit status of zero (succeeded) or not, for example

command && echo "command succeeded" || echo "command failed"

Here's an excerpt from man bash:

AND and OR lists are sequences of one or more pipelines separated by
the && and || control operators, respectively. AND and OR lists are
executed with left associativity. An AND list has the form
 command1 && command2
command2 is executed if, and only if, command1 returns an exit status
of zero.

An OR list has the form
 command1 || command2
command2 is executed if and only if command1 returns a non-zero exit
status. The return status of AND and OR lists is the exit status of
the last command executed in the list.

You could combine them, and also see the exit status if you want, with your example like:

sudo mount 192.168.0.2:/home/dk/NFS /home/dk/NFS && 
echo "NFS mounted OK" || echo "Mounting NFS failed: $?"

answered 18 mins ago

Xen2050

6,46912142

add a commentÂ |Â

up vote
0
down vote

In addition to Sergiy's good answer, you could consider using AND and OR lists to quickly check if a command returns an exit status of zero (succeeded) or not, for example

command && echo "command succeeded" || echo "command failed"

Here's an excerpt from man bash:

AND and OR lists are sequences of one or more pipelines separated by
the && and || control operators, respectively. AND and OR lists are
executed with left associativity. An AND list has the form
 command1 && command2
command2 is executed if, and only if, command1 returns an exit status
of zero.

An OR list has the form
 command1 || command2
command2 is executed if and only if command1 returns a non-zero exit
status. The return status of AND and OR lists is the exit status of
the last command executed in the list.

You could combine them, and also see the exit status if you want, with your example like:

sudo mount 192.168.0.2:/home/dk/NFS /home/dk/NFS && 
echo "NFS mounted OK" || echo "Mounting NFS failed: $?"

answered 18 mins ago

Xen2050

6,46912142

add a commentÂ |Â

up vote
0
down vote

In addition to Sergiy's good answer, you could consider using AND and OR lists to quickly check if a command returns an exit status of zero (succeeded) or not, for example

command && echo "command succeeded" || echo "command failed"

Here's an excerpt from man bash:

AND and OR lists are sequences of one or more pipelines separated by
the && and || control operators, respectively. AND and OR lists are
executed with left associativity. An AND list has the form
 command1 && command2
command2 is executed if, and only if, command1 returns an exit status
of zero.

An OR list has the form
 command1 || command2
command2 is executed if and only if command1 returns a non-zero exit
status. The return status of AND and OR lists is the exit status of
the last command executed in the list.

You could combine them, and also see the exit status if you want, with your example like:

sudo mount 192.168.0.2:/home/dk/NFS /home/dk/NFS && 
echo "NFS mounted OK" || echo "Mounting NFS failed: $?"

answered 18 mins ago

Xen2050

6,46912142

In addition to Sergiy's good answer, you could consider using AND and OR lists to quickly check if a command returns an exit status of zero (succeeded) or not, for example

command && echo "command succeeded" || echo "command failed"

Here's an excerpt from man bash:

AND and OR lists are sequences of one or more pipelines separated by
the && and || control operators, respectively. AND and OR lists are
executed with left associativity. An AND list has the form
 command1 && command2
command2 is executed if, and only if, command1 returns an exit status
of zero.

An OR list has the form
 command1 || command2
command2 is executed if and only if command1 returns a non-zero exit
status. The return status of AND and OR lists is the exit status of
the last command executed in the list.

You could combine them, and also see the exit status if you want, with your example like:

sudo mount 192.168.0.2:/home/dk/NFS /home/dk/NFS && 
echo "NFS mounted OK" || echo "Mounting NFS failed: $?"

answered 18 mins ago

Xen2050

6,46912142

answered 18 mins ago

Xen2050

6,46912142

answered 18 mins ago

Xen2050

6,46912142

answered 18 mins ago

Xen2050

6,46912142

add a commentÂ |Â

draft saved

draft discarded

draft saved

draft discarded

Post as a guest

Name

Search This Blog

Iyfjky