How can I make environment variables “exported” in a shell script stick around?
I have multiple Amazon EC2 accounts and want to quickly be able to switch variables, such as $EC2_HOME, using a script.
I have have a shell script set up like this:
#!/bin/sh
export EC2_HOME=/home/me/.ec2
echo $EC2_HOME
When I run the script I know that EC2_HOME is set, but I thought that using export would make the variable stick around after the script completed. It does not, as running echo $EC_HOME does not show anything.
I know this must be very rudimentary Linux scripting knowledge, but I don't know it. I tried looking for related questions without luck - so my apologies if this is a duplicate.
bash shell-script shell environment-variables
edited Nov 27 '16 at 20:32
Michael Homer
47.4k8124162
asked Jan 27 '12 at 19:32
cwdcwd
13.7k52115157
add a comment |
I have multiple Amazon EC2 accounts and want to quickly be able to switch variables, such as $EC2_HOME, using a script.
I have have a shell script set up like this:
#!/bin/sh
export EC2_HOME=/home/me/.ec2
echo $EC2_HOME
When I run the script I know that EC2_HOME is set, but I thought that using export would make the variable stick around after the script completed. It does not, as running echo $EC_HOME does not show anything.
I know this must be very rudimentary Linux scripting knowledge, but I don't know it. I tried looking for related questions without luck - so my apologies if this is a duplicate.
bash shell-script shell environment-variables
edited Nov 27 '16 at 20:32
Michael Homer
47.4k8124162
asked Jan 27 '12 at 19:32
cwdcwd
13.7k52115157
add a comment |
I have multiple Amazon EC2 accounts and want to quickly be able to switch variables, such as $EC2_HOME, using a script.
I have have a shell script set up like this:
#!/bin/sh
export EC2_HOME=/home/me/.ec2
echo $EC2_HOME
When I run the script I know that EC2_HOME is set, but I thought that using export would make the variable stick around after the script completed. It does not, as running echo $EC_HOME does not show anything.
I know this must be very rudimentary Linux scripting knowledge, but I don't know it. I tried looking for related questions without luck - so my apologies if this is a duplicate.
bash shell-script shell environment-variables
edited Nov 27 '16 at 20:32
Michael Homer
47.4k8124162
asked Jan 27 '12 at 19:32
cwdcwd
13.7k52115157
I have multiple Amazon EC2 accounts and want to quickly be able to switch variables, such as $EC2_HOME, using a script.
I have have a shell script set up like this:
#!/bin/sh
export EC2_HOME=/home/me/.ec2
echo $EC2_HOME
When I run the script I know that EC2_HOME is set, but I thought that using export would make the variable stick around after the script completed. It does not, as running echo $EC_HOME does not show anything.
I know this must be very rudimentary Linux scripting knowledge, but I don't know it. I tried looking for related questions without luck - so my apologies if this is a duplicate.
bash shell-script shell environment-variables
bash shell-script shell environment-variables
edited Nov 27 '16 at 20:32
Michael Homer
47.4k8124162
asked Jan 27 '12 at 19:32
cwdcwd
13.7k52115157
edited Nov 27 '16 at 20:32
Michael Homer
47.4k8124162
asked Jan 27 '12 at 19:32
cwdcwd
13.7k52115157
edited Nov 27 '16 at 20:32
Michael Homer
47.4k8124162
edited Nov 27 '16 at 20:32
Michael Homer
47.4k8124162
edited Nov 27 '16 at 20:32
Michael Homer
47.4k8124162
47.4k8124162
asked Jan 27 '12 at 19:32
cwdcwd
13.7k52115157
asked Jan 27 '12 at 19:32
cwdcwd
13.7k52115157
asked Jan 27 '12 at 19:32
cwdcwd
13.7k52115157
13.7k52115157
add a comment |
add a comment |
2 Answers
2
active
oldest
votes
You should source your script, with
. ./script
or
source ./script
answered Jan 27 '12 at 20:12
enzotibenzotib
33.8k710395
19
the reason is that your script spawns a new shell process as a child of the current shell. Any environment changes you make in the child process cannot affect the parent. When you use.orsource, you are not spawning a new child process, you are running the commands in the current shell.
– glenn jackman
Jan 27 '12 at 20:32
1
@glennjackman I have a similar problem and I have tried your solution but it logs me off from shell when I do.orsource. Why is this happening ?
– Patryk
Feb 21 '12 at 13:03
7
@Patryk: maybe your script has anexitstatement, so it is not suitable to be sourced.
– enzotib
Feb 21 '12 at 13:24
Whilesource ./scriptworks completely fine,sudo source ./script.shsayssudo: source: command not found. How can I do this using sudo?
– 71GA
Sep 27 '14 at 13:37
1
@71GA: depending on compilation preferences forsudoand depending on configuration settings in/etc/sudoersyou can or cannot preserve your environment when running commands withsudo. I suggest you to try to source your script, and then runsudowith-Eoption to preserve the environment. If it does not work, I suppose there is very little you can do.
– enzotib
Sep 27 '14 at 13:52
|
show 1 more comment
When you run a script it gets its own shell and its own environment, which disappear again as soon as the script is finished. To keep the environment variables around, source the script into your current shell:
$ source ./a.sh
or equivalently (but a little more portably) use the POSIX dot command:
$ . ./a.sh
Then the definitions will be put into your current shell's environment and be inherited by any programs you launch from it.
To be closer to running a script, . a.sh will find a.sh by searching the directories in the PATH environment variable.
There are some subtleties in how these behave, and whether . and source are the same (or present at all). . ./a.sh will definitely behave the same in every POSIX-compatible shell, but source and ., and . a.sh and . ./a.sh, can vary. For Bash source and . are the same in all cases; for zsh source always checks the current directory first; ksh is essentially similar.
If the script name is given as a path (containing a /), that path is used directly in all cases. The most portably reliable thing to do is . ./script or . /path/to/script.
answered Jun 27 '14 at 0:07
Michael HomerMichael Homer
47.4k8124162
add a comment |
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2 Answers
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active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
You should source your script, with
. ./script
or
source ./script
answered Jan 27 '12 at 20:12
enzotibenzotib
33.8k710395
19
the reason is that your script spawns a new shell process as a child of the current shell. Any environment changes you make in the child process cannot affect the parent. When you use.orsource, you are not spawning a new child process, you are running the commands in the current shell.
– glenn jackman
Jan 27 '12 at 20:32
1
@glennjackman I have a similar problem and I have tried your solution but it logs me off from shell when I do.orsource. Why is this happening ?
– Patryk
Feb 21 '12 at 13:03
7
@Patryk: maybe your script has anexitstatement, so it is not suitable to be sourced.
– enzotib
Feb 21 '12 at 13:24
Whilesource ./scriptworks completely fine,sudo source ./script.shsayssudo: source: command not found. How can I do this using sudo?
– 71GA
Sep 27 '14 at 13:37
1
@71GA: depending on compilation preferences forsudoand depending on configuration settings in/etc/sudoersyou can or cannot preserve your environment when running commands withsudo. I suggest you to try to source your script, and then runsudowith-Eoption to preserve the environment. If it does not work, I suppose there is very little you can do.
– enzotib
Sep 27 '14 at 13:52
|
show 1 more comment
You should source your script, with
. ./script
or
source ./script
answered Jan 27 '12 at 20:12
enzotibenzotib
33.8k710395
19
the reason is that your script spawns a new shell process as a child of the current shell. Any environment changes you make in the child process cannot affect the parent. When you use.orsource, you are not spawning a new child process, you are running the commands in the current shell.
– glenn jackman
Jan 27 '12 at 20:32
1
@glennjackman I have a similar problem and I have tried your solution but it logs me off from shell when I do.orsource. Why is this happening ?
– Patryk
Feb 21 '12 at 13:03
7
@Patryk: maybe your script has anexitstatement, so it is not suitable to be sourced.
– enzotib
Feb 21 '12 at 13:24
Whilesource ./scriptworks completely fine,sudo source ./script.shsayssudo: source: command not found. How can I do this using sudo?
– 71GA
Sep 27 '14 at 13:37
1
@71GA: depending on compilation preferences forsudoand depending on configuration settings in/etc/sudoersyou can or cannot preserve your environment when running commands withsudo. I suggest you to try to source your script, and then runsudowith-Eoption to preserve the environment. If it does not work, I suppose there is very little you can do.
– enzotib
Sep 27 '14 at 13:52
|
show 1 more comment
You should source your script, with
. ./script
or
source ./script
answered Jan 27 '12 at 20:12
enzotibenzotib
33.8k710395
You should source your script, with
. ./script
or
source ./script
answered Jan 27 '12 at 20:12
enzotibenzotib
33.8k710395
answered Jan 27 '12 at 20:12
enzotibenzotib
33.8k710395
answered Jan 27 '12 at 20:12
enzotibenzotib
33.8k710395
answered Jan 27 '12 at 20:12
enzotibenzotib
33.8k710395
33.8k710395
19
the reason is that your script spawns a new shell process as a child of the current shell. Any environment changes you make in the child process cannot affect the parent. When you use.orsource, you are not spawning a new child process, you are running the commands in the current shell.
– glenn jackman
Jan 27 '12 at 20:32
1
@glennjackman I have a similar problem and I have tried your solution but it logs me off from shell when I do.orsource. Why is this happening ?
– Patryk
Feb 21 '12 at 13:03
7
@Patryk: maybe your script has anexitstatement, so it is not suitable to be sourced.
– enzotib
Feb 21 '12 at 13:24
Whilesource ./scriptworks completely fine,sudo source ./script.shsayssudo: source: command not found. How can I do this using sudo?
– 71GA
Sep 27 '14 at 13:37
1
@71GA: depending on compilation preferences forsudoand depending on configuration settings in/etc/sudoersyou can or cannot preserve your environment when running commands withsudo. I suggest you to try to source your script, and then runsudowith-Eoption to preserve the environment. If it does not work, I suppose there is very little you can do.
– enzotib
Sep 27 '14 at 13:52
|
show 1 more comment
19
the reason is that your script spawns a new shell process as a child of the current shell. Any environment changes you make in the child process cannot affect the parent. When you use.orsource, you are not spawning a new child process, you are running the commands in the current shell.
– glenn jackman
Jan 27 '12 at 20:32
1
@glennjackman I have a similar problem and I have tried your solution but it logs me off from shell when I do.orsource. Why is this happening ?
– Patryk
Feb 21 '12 at 13:03
7
@Patryk: maybe your script has anexitstatement, so it is not suitable to be sourced.
– enzotib
Feb 21 '12 at 13:24
Whilesource ./scriptworks completely fine,sudo source ./script.shsayssudo: source: command not found. How can I do this using sudo?
– 71GA
Sep 27 '14 at 13:37
1
@71GA: depending on compilation preferences forsudoand depending on configuration settings in/etc/sudoersyou can or cannot preserve your environment when running commands withsudo. I suggest you to try to source your script, and then runsudowith-Eoption to preserve the environment. If it does not work, I suppose there is very little you can do.
– enzotib
Sep 27 '14 at 13:52
19
19
the reason is that your script spawns a new shell process as a child of the current shell. Any environment changes you make in the child process cannot affect the parent. When you use
. or source, you are not spawning a new child process, you are running the commands in the current shell.– glenn jackman
Jan 27 '12 at 20:32
the reason is that your script spawns a new shell process as a child of the current shell. Any environment changes you make in the child process cannot affect the parent. When you use
. or source, you are not spawning a new child process, you are running the commands in the current shell.– glenn jackman
Jan 27 '12 at 20:32
1
1
@glennjackman I have a similar problem and I have tried your solution but it logs me off from shell when I do
. or source. Why is this happening ?– Patryk
Feb 21 '12 at 13:03
@glennjackman I have a similar problem and I have tried your solution but it logs me off from shell when I do
. or source. Why is this happening ?– Patryk
Feb 21 '12 at 13:03
7
7
@Patryk: maybe your script has an
exit statement, so it is not suitable to be sourced.– enzotib
Feb 21 '12 at 13:24
@Patryk: maybe your script has an
exit statement, so it is not suitable to be sourced.– enzotib
Feb 21 '12 at 13:24
While
source ./script works completely fine, sudo source ./script.sh says sudo: source: command not found. How can I do this using sudo?– 71GA
Sep 27 '14 at 13:37
While
source ./script works completely fine, sudo source ./script.sh says sudo: source: command not found. How can I do this using sudo?– 71GA
Sep 27 '14 at 13:37
1
1
@71GA: depending on compilation preferences for
sudo and depending on configuration settings in /etc/sudoers you can or cannot preserve your environment when running commands with sudo. I suggest you to try to source your script, and then run sudo with -E option to preserve the environment. If it does not work, I suppose there is very little you can do.– enzotib
Sep 27 '14 at 13:52
@71GA: depending on compilation preferences for
sudo and depending on configuration settings in /etc/sudoers you can or cannot preserve your environment when running commands with sudo. I suggest you to try to source your script, and then run sudo with -E option to preserve the environment. If it does not work, I suppose there is very little you can do.– enzotib
Sep 27 '14 at 13:52
|
show 1 more comment
When you run a script it gets its own shell and its own environment, which disappear again as soon as the script is finished. To keep the environment variables around, source the script into your current shell:
$ source ./a.sh
or equivalently (but a little more portably) use the POSIX dot command:
$ . ./a.sh
Then the definitions will be put into your current shell's environment and be inherited by any programs you launch from it.
To be closer to running a script, . a.sh will find a.sh by searching the directories in the PATH environment variable.
There are some subtleties in how these behave, and whether . and source are the same (or present at all). . ./a.sh will definitely behave the same in every POSIX-compatible shell, but source and ., and . a.sh and . ./a.sh, can vary. For Bash source and . are the same in all cases; for zsh source always checks the current directory first; ksh is essentially similar.
If the script name is given as a path (containing a /), that path is used directly in all cases. The most portably reliable thing to do is . ./script or . /path/to/script.
answered Jun 27 '14 at 0:07
Michael HomerMichael Homer
47.4k8124162
add a comment |
When you run a script it gets its own shell and its own environment, which disappear again as soon as the script is finished. To keep the environment variables around, source the script into your current shell:
$ source ./a.sh
or equivalently (but a little more portably) use the POSIX dot command:
$ . ./a.sh
Then the definitions will be put into your current shell's environment and be inherited by any programs you launch from it.
To be closer to running a script, . a.sh will find a.sh by searching the directories in the PATH environment variable.
There are some subtleties in how these behave, and whether . and source are the same (or present at all). . ./a.sh will definitely behave the same in every POSIX-compatible shell, but source and ., and . a.sh and . ./a.sh, can vary. For Bash source and . are the same in all cases; for zsh source always checks the current directory first; ksh is essentially similar.
If the script name is given as a path (containing a /), that path is used directly in all cases. The most portably reliable thing to do is . ./script or . /path/to/script.
answered Jun 27 '14 at 0:07
Michael HomerMichael Homer
47.4k8124162
add a comment |
When you run a script it gets its own shell and its own environment, which disappear again as soon as the script is finished. To keep the environment variables around, source the script into your current shell:
$ source ./a.sh
or equivalently (but a little more portably) use the POSIX dot command:
$ . ./a.sh
Then the definitions will be put into your current shell's environment and be inherited by any programs you launch from it.
To be closer to running a script, . a.sh will find a.sh by searching the directories in the PATH environment variable.
There are some subtleties in how these behave, and whether . and source are the same (or present at all). . ./a.sh will definitely behave the same in every POSIX-compatible shell, but source and ., and . a.sh and . ./a.sh, can vary. For Bash source and . are the same in all cases; for zsh source always checks the current directory first; ksh is essentially similar.
If the script name is given as a path (containing a /), that path is used directly in all cases. The most portably reliable thing to do is . ./script or . /path/to/script.
answered Jun 27 '14 at 0:07
Michael HomerMichael Homer
47.4k8124162
When you run a script it gets its own shell and its own environment, which disappear again as soon as the script is finished. To keep the environment variables around, source the script into your current shell:
$ source ./a.sh
or equivalently (but a little more portably) use the POSIX dot command:
$ . ./a.sh
Then the definitions will be put into your current shell's environment and be inherited by any programs you launch from it.
To be closer to running a script, . a.sh will find a.sh by searching the directories in the PATH environment variable.
There are some subtleties in how these behave, and whether . and source are the same (or present at all). . ./a.sh will definitely behave the same in every POSIX-compatible shell, but source and ., and . a.sh and . ./a.sh, can vary. For Bash source and . are the same in all cases; for zsh source always checks the current directory first; ksh is essentially similar.
If the script name is given as a path (containing a /), that path is used directly in all cases. The most portably reliable thing to do is . ./script or . /path/to/script.
answered Jun 27 '14 at 0:07
Michael HomerMichael Homer
47.4k8124162
edited Nov 28 '16 at 0:01
answered Jun 27 '14 at 0:07
Michael HomerMichael Homer
47.4k8124162
answered Jun 27 '14 at 0:07
Michael HomerMichael Homer
47.4k8124162
answered Jun 27 '14 at 0:07
Michael HomerMichael Homer
47.4k8124162
47.4k8124162
add a comment |
add a comment |
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