Bash – Multiple path environment variable setup lines with bash

bashenvironment-variablespath

I have very long export PATH=A:B:C .... Can I make a multiple lines to have more organized one as follows?

export PATH = A:
              B:
              C:

Best Answer

You can do:

export PATH="A"
export PATH="$PATH:B"
export PATH="$PATH:C"

Each subsequent line appends onto the previously defined path. This is generally a good habit, as it avoids trashing the existing path. If you want the new component to take precedence, swap the order:

export PATH="A"
export PATH="B:$PATH"
export PATH="C:$PATH"

Alternatively, you might be able to do:

export PATH=A:\
B:\ 
C

where \ marks a line continuation. Haven't tested this method.

Related Solutions

Shell – Percent in $PATH environment variable

That's not the Bourne shell, or bash emulating the Bourne shell, that's the Almquist shell, in your case probably the Debian Almquist shell (a Linux fork by Debian of BSDs' sh itself based on the original Almquist shell).

In the Almquist shell (the original one and the modern versions), % is used in PATH for extra features specific to ash. Quoting from the documentation:

Path Search

When locating a command, the shell first looks to see if it has a shell function by that name. Then, if PATH does not contain an entry for %builtin, it looks for a builtin command by that name. Finally, it searches each entry in PATH in turn for the command.

The value of the PATH variable should be a series of entries separated by colons. Each entry consists of a directory name, or a directory name followed by a flag beginning with a percent sign. The current directory should be indicated by an empty directory name. If no percent sign is present, then the entry causes the shell to search for the command in the specified directory. If the flag is %builtin then the list of shell builtin commands is searched. If the flag is %func then the directory is searched for a file which is read as input to the shell. This file should define a function whose name is the name of the command being searched for.

Command names containing a slash are simply executed without performing any of the above searches.

Other shells like ksh or zsh have a similar autoloading of functions mechanism, but they use a different variable ($FPATH), but you can't define which of functions or executables take precedence.

In your case, /home/torbjorr/deployed/vector/x86_64-GNU%2fLinux is interpreted as the /home/torbjorr/deployed/vector/x86_64-GNU directory with the 2fLinux flag. That flag is ignored as it is unknown.

There is no way around that. Even if ash had an escape mechanism so that this % not be treated specially, it would then not work in other shells or other things that look up $PATH like execvp().

You'll need to remove the % characters from $PATH, so rename your directory or add a symlink.

Or don't use ash for your /bin/sh. Other lightweight POSIX shell implementations that don't do that include yash and mksh.

Bash – Using a bash alias or function with environment variables on multiple lines

The alias actually seems to work for me like that (provided that there's no whitespace after the backslashes). But a function might be nicer and at least makes it easier to use single-quotes:

staging_server() {
    MY_ENV1='http://example.com' \
    MY_ENV2="..." \
    start_server -p 1234 "$@"
}

Best Answer

Related Solutions

Shell – Percent in $PATH environment variable

Bash – Using a bash alias or function with environment variables on multiple lines

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