cat output in the case of if else statement
os_version=$(cat /etc/issue |grep Ubuntu)
if $os_version
then
echo found
else
echo notfound
fi
When I tried it on an Ubuntu machine it says
./test: line 2: Ubuntu: command not found
notfound
This works for me, But I want to assign it to a variable
if cat /etc/issue |grep Ubuntu
then
echo found
else
echo notfound
fi
shell-script shell
edited Nov 13 at 16:56
Rui F Ribeiro
38.8k1479128
asked Nov 12 at 12:18
HistoriaReiss
113
add a comment |
os_version=$(cat /etc/issue |grep Ubuntu)
if $os_version
then
echo found
else
echo notfound
fi
When I tried it on an Ubuntu machine it says
./test: line 2: Ubuntu: command not found
notfound
This works for me, But I want to assign it to a variable
if cat /etc/issue |grep Ubuntu
then
echo found
else
echo notfound
fi
shell-script shell
edited Nov 13 at 16:56
Rui F Ribeiro
38.8k1479128
asked Nov 12 at 12:18
HistoriaReiss
113
What did you intend with the "if" test? By default, it expects to execute a command and test that return code, which is why it told you it tried to execute a command that started with "Ubuntu...". Are you interested in whether /etc/issue contains the word "Ubuntu" or are you trying to do something else?
– Jeff Schaller
Nov 12 at 12:21
I am interested to know if /etc/issue contains Ubuntu,I would like to assign it to a variable and check
– HistoriaReiss
Nov 12 at 12:27
If you want to know whether or not /etc/issue contains Ubuntu, why do you want to assign anything to a variable? Just check the status ofgrep.
– William Pursell
Nov 12 at 12:46
2
Of course, if the "Ubuntu" in your login banner is coming from anSin/etc/issue, none of this will pick it up. (-:
– JdeBP
Nov 12 at 16:21
add a comment |
os_version=$(cat /etc/issue |grep Ubuntu)
if $os_version
then
echo found
else
echo notfound
fi
When I tried it on an Ubuntu machine it says
./test: line 2: Ubuntu: command not found
notfound
This works for me, But I want to assign it to a variable
if cat /etc/issue |grep Ubuntu
then
echo found
else
echo notfound
fi
shell-script shell
edited Nov 13 at 16:56
Rui F Ribeiro
38.8k1479128
asked Nov 12 at 12:18
HistoriaReiss
113
os_version=$(cat /etc/issue |grep Ubuntu)
if $os_version
then
echo found
else
echo notfound
fi
When I tried it on an Ubuntu machine it says
./test: line 2: Ubuntu: command not found
notfound
This works for me, But I want to assign it to a variable
if cat /etc/issue |grep Ubuntu
then
echo found
else
echo notfound
fi
shell-script shell
shell-script shell
edited Nov 13 at 16:56
Rui F Ribeiro
38.8k1479128
asked Nov 12 at 12:18
HistoriaReiss
113
edited Nov 13 at 16:56
Rui F Ribeiro
38.8k1479128
asked Nov 12 at 12:18
HistoriaReiss
113
edited Nov 13 at 16:56
Rui F Ribeiro
38.8k1479128
edited Nov 13 at 16:56
Rui F Ribeiro
38.8k1479128
edited Nov 13 at 16:56
Rui F Ribeiro
38.8k1479128
38.8k1479128
asked Nov 12 at 12:18
HistoriaReiss
113
asked Nov 12 at 12:18
HistoriaReiss
113
asked Nov 12 at 12:18
HistoriaReiss
113
113
What did you intend with the "if" test? By default, it expects to execute a command and test that return code, which is why it told you it tried to execute a command that started with "Ubuntu...". Are you interested in whether /etc/issue contains the word "Ubuntu" or are you trying to do something else?
– Jeff Schaller
Nov 12 at 12:21
I am interested to know if /etc/issue contains Ubuntu,I would like to assign it to a variable and check
– HistoriaReiss
Nov 12 at 12:27
If you want to know whether or not /etc/issue contains Ubuntu, why do you want to assign anything to a variable? Just check the status ofgrep.
– William Pursell
Nov 12 at 12:46
2
Of course, if the "Ubuntu" in your login banner is coming from anSin/etc/issue, none of this will pick it up. (-:
– JdeBP
Nov 12 at 16:21
add a comment |
What did you intend with the "if" test? By default, it expects to execute a command and test that return code, which is why it told you it tried to execute a command that started with "Ubuntu...". Are you interested in whether /etc/issue contains the word "Ubuntu" or are you trying to do something else?
– Jeff Schaller
Nov 12 at 12:21
I am interested to know if /etc/issue contains Ubuntu,I would like to assign it to a variable and check
– HistoriaReiss
Nov 12 at 12:27
If you want to know whether or not /etc/issue contains Ubuntu, why do you want to assign anything to a variable? Just check the status ofgrep.
– William Pursell
Nov 12 at 12:46
2
Of course, if the "Ubuntu" in your login banner is coming from anSin/etc/issue, none of this will pick it up. (-:
– JdeBP
Nov 12 at 16:21
What did you intend with the "if" test? By default, it expects to execute a command and test that return code, which is why it told you it tried to execute a command that started with "Ubuntu...". Are you interested in whether /etc/issue contains the word "Ubuntu" or are you trying to do something else?
– Jeff Schaller
Nov 12 at 12:21
What did you intend with the "if" test? By default, it expects to execute a command and test that return code, which is why it told you it tried to execute a command that started with "Ubuntu...". Are you interested in whether /etc/issue contains the word "Ubuntu" or are you trying to do something else?
– Jeff Schaller
Nov 12 at 12:21
I am interested to know if /etc/issue contains Ubuntu,I would like to assign it to a variable and check
– HistoriaReiss
Nov 12 at 12:27
I am interested to know if /etc/issue contains Ubuntu,I would like to assign it to a variable and check
– HistoriaReiss
Nov 12 at 12:27
If you want to know whether or not /etc/issue contains Ubuntu, why do you want to assign anything to a variable? Just check the status of
grep.– William Pursell
Nov 12 at 12:46
If you want to know whether or not /etc/issue contains Ubuntu, why do you want to assign anything to a variable? Just check the status of
grep.– William Pursell
Nov 12 at 12:46
2
2
Of course, if the "Ubuntu" in your login banner is coming from an
S in /etc/issue, none of this will pick it up. (-:– JdeBP
Nov 12 at 16:21
Of course, if the "Ubuntu" in your login banner is coming from an
S in /etc/issue, none of this will pick it up. (-:– JdeBP
Nov 12 at 16:21
add a comment |
2 Answers
2
active
oldest
votes
The if statement runs a command, and checks its exit status.
Using $os_version as a command works by expanding it, and running the resulting command line. So if the variable contains Ubuntu 18.04.1 LTS n l, it'll try to to run a command called Ubuntu with the arguments 18.04.1, LTS, etc.
You probably want to use
if [ -n "$os_version" ]; then
...
fi
to check if the variable is empty or not ([ -n "$var" ] is true if it's not empty, while [ -z "$var" ] if the variable is empty).
Alternatively, you could use the grep within the if statement itself as you did in the edit, and set a variable there:
distro=unknown
if grep -q Ubuntu < /etc/issue; then
distro=ubuntu
fi
# ... later
if [ "$distro" = ubuntu ]; then
# do something Ubuntu-specific
fi
answered Nov 12 at 12:37
ilkkachu
55.4k782150
add a comment |
grep -q Ubuntu /etc/issue && echo found || echo not found
answered Nov 12 at 12:22
Ipor Sircer
10.5k11024
2
See alsocase $(lsb_release -si) in (Ubuntu) ...;; (Debian) ...; esac
– Stéphane Chazelas
Nov 12 at 12:23
add a comment |
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2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
The if statement runs a command, and checks its exit status.
Using $os_version as a command works by expanding it, and running the resulting command line. So if the variable contains Ubuntu 18.04.1 LTS n l, it'll try to to run a command called Ubuntu with the arguments 18.04.1, LTS, etc.
You probably want to use
if [ -n "$os_version" ]; then
...
fi
to check if the variable is empty or not ([ -n "$var" ] is true if it's not empty, while [ -z "$var" ] if the variable is empty).
Alternatively, you could use the grep within the if statement itself as you did in the edit, and set a variable there:
distro=unknown
if grep -q Ubuntu < /etc/issue; then
distro=ubuntu
fi
# ... later
if [ "$distro" = ubuntu ]; then
# do something Ubuntu-specific
fi
answered Nov 12 at 12:37
ilkkachu
55.4k782150
add a comment |
The if statement runs a command, and checks its exit status.
Using $os_version as a command works by expanding it, and running the resulting command line. So if the variable contains Ubuntu 18.04.1 LTS n l, it'll try to to run a command called Ubuntu with the arguments 18.04.1, LTS, etc.
You probably want to use
if [ -n "$os_version" ]; then
...
fi
to check if the variable is empty or not ([ -n "$var" ] is true if it's not empty, while [ -z "$var" ] if the variable is empty).
Alternatively, you could use the grep within the if statement itself as you did in the edit, and set a variable there:
distro=unknown
if grep -q Ubuntu < /etc/issue; then
distro=ubuntu
fi
# ... later
if [ "$distro" = ubuntu ]; then
# do something Ubuntu-specific
fi
answered Nov 12 at 12:37
ilkkachu
55.4k782150
add a comment |
The if statement runs a command, and checks its exit status.
Using $os_version as a command works by expanding it, and running the resulting command line. So if the variable contains Ubuntu 18.04.1 LTS n l, it'll try to to run a command called Ubuntu with the arguments 18.04.1, LTS, etc.
You probably want to use
if [ -n "$os_version" ]; then
...
fi
to check if the variable is empty or not ([ -n "$var" ] is true if it's not empty, while [ -z "$var" ] if the variable is empty).
Alternatively, you could use the grep within the if statement itself as you did in the edit, and set a variable there:
distro=unknown
if grep -q Ubuntu < /etc/issue; then
distro=ubuntu
fi
# ... later
if [ "$distro" = ubuntu ]; then
# do something Ubuntu-specific
fi
answered Nov 12 at 12:37
ilkkachu
55.4k782150
The if statement runs a command, and checks its exit status.
Using $os_version as a command works by expanding it, and running the resulting command line. So if the variable contains Ubuntu 18.04.1 LTS n l, it'll try to to run a command called Ubuntu with the arguments 18.04.1, LTS, etc.
You probably want to use
if [ -n "$os_version" ]; then
...
fi
to check if the variable is empty or not ([ -n "$var" ] is true if it's not empty, while [ -z "$var" ] if the variable is empty).
Alternatively, you could use the grep within the if statement itself as you did in the edit, and set a variable there:
distro=unknown
if grep -q Ubuntu < /etc/issue; then
distro=ubuntu
fi
# ... later
if [ "$distro" = ubuntu ]; then
# do something Ubuntu-specific
fi
answered Nov 12 at 12:37
ilkkachu
55.4k782150
answered Nov 12 at 12:37
ilkkachu
55.4k782150
answered Nov 12 at 12:37
ilkkachu
55.4k782150
answered Nov 12 at 12:37
ilkkachu
55.4k782150
55.4k782150
add a comment |
add a comment |
grep -q Ubuntu /etc/issue && echo found || echo not found
answered Nov 12 at 12:22
Ipor Sircer
10.5k11024
2
See alsocase $(lsb_release -si) in (Ubuntu) ...;; (Debian) ...; esac
– Stéphane Chazelas
Nov 12 at 12:23
add a comment |
grep -q Ubuntu /etc/issue && echo found || echo not found
answered Nov 12 at 12:22
Ipor Sircer
10.5k11024
2
See alsocase $(lsb_release -si) in (Ubuntu) ...;; (Debian) ...; esac
– Stéphane Chazelas
Nov 12 at 12:23
add a comment |
grep -q Ubuntu /etc/issue && echo found || echo not found
answered Nov 12 at 12:22
Ipor Sircer
10.5k11024
grep -q Ubuntu /etc/issue && echo found || echo not found
answered Nov 12 at 12:22
Ipor Sircer
10.5k11024
answered Nov 12 at 12:22
Ipor Sircer
10.5k11024
answered Nov 12 at 12:22
Ipor Sircer
10.5k11024
answered Nov 12 at 12:22
Ipor Sircer
10.5k11024
10.5k11024
2
See alsocase $(lsb_release -si) in (Ubuntu) ...;; (Debian) ...; esac
– Stéphane Chazelas
Nov 12 at 12:23
add a comment |
2
See alsocase $(lsb_release -si) in (Ubuntu) ...;; (Debian) ...; esac
– Stéphane Chazelas
Nov 12 at 12:23
2
2
See also
case $(lsb_release -si) in (Ubuntu) ...;; (Debian) ...; esac– Stéphane Chazelas
Nov 12 at 12:23
See also
case $(lsb_release -si) in (Ubuntu) ...;; (Debian) ...; esac– Stéphane Chazelas
Nov 12 at 12:23
add a comment |
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What did you intend with the "if" test? By default, it expects to execute a command and test that return code, which is why it told you it tried to execute a command that started with "Ubuntu...". Are you interested in whether /etc/issue contains the word "Ubuntu" or are you trying to do something else?
– Jeff Schaller
Nov 12 at 12:21
I am interested to know if /etc/issue contains Ubuntu,I would like to assign it to a variable and check
– HistoriaReiss
Nov 12 at 12:27
If you want to know whether or not /etc/issue contains Ubuntu, why do you want to assign anything to a variable? Just check the status of
grep.– William Pursell
Nov 12 at 12:46
2
Of course, if the "Ubuntu" in your login banner is coming from an
Sin/etc/issue, none of this will pick it up. (-:– JdeBP
Nov 12 at 16:21