When to use the IFS variable in Bash?
cat -etv <<<“$IFS” IFS variable is commonly used with read command, parameter expansions and command substitution. From the bash man page: The shell treats each character of IFS as a delimiter, and splits the results of the other expansions into words on these characters.
What is the default value for IFS in Linux?
The Internal Field Separator (IFS) that is used for word splitting after expansion and to split lines into words with the read builtin command. The default value is .
What’s the default value for the IFS separator?
The Internal Field Separator (IFS) that is used for word splitting after expansion and to split lines into words with the read builtin command. The default value is . You can print it with the following command:
What is the name of the variable in Bash?
So, this particular line assigns newline to the variable IFS. IFS, in turn, is a special variable in bash: Internal Field Separator. As man bash says, it. is used for word splitting after expansion and to split lines into words with the read builtin command.
When do you ignore whitespace in IFS script?
If IFS has a value other than the default, then sequences of the whitespace characters space and tab are ignored at the beginning and end of the word, as long as the whitespace character is in the value of IFS (an IFS whitespace character).
What does IFS = read-R Line mean in Bash?
So when doing IFS= read -r line, what you are doing is setting IFS to an empty string (no character will be used to split, therefore no splitting will occur) so that read will read the entire line and see it as one word that will be assigned to the line variable.
For example, is translated to new line. So, this particular line assigns newline to the variable IFS. IFS, in turn, is a special variable in bash: Internal Field Separator. As man bash says, it is used for word splitting after expansion and to split lines into words with the read builtin command.
How to know the exact meaning of IFS?
You should double quote it to avoid line breaking such as OLDIFS=”$IFS”. ANSI C-quoted strings is a key point. Thanks to @mklement0 . You can test ANSI C-quoted strings with command od. You can know the meaning clearly by the outputs.