sh - split string by delimiter

Question

code

s='id;some text here with possible ; inside'
IFS=';' read -r id string <<< "$s"
echo "$id"

error

restore.sh: 2: restore.sh: Syntax error: redirection unexpected

bash version GNU bash, version 4.2.37(1)-release (x86_64-pc-linux-gnu)

Working to me on `GNU bash, version 4.2.45(1)-release (x86_64-pc-linux-gnu)` — fedorqui, Nov 12 '13 at 13:45

score 11 · Answer 1 · answered Nov 12 '13 at 14:38

11

A here string is just a shortcut for a small here document. This should work in any POSIX shell:

s='id;some text here with possible ; inside'
IFS=';' read -r id string <<EOF
$s
EOF
echo "$id"

answered Nov 12 '13 at 14:38

chepner

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Am new to shell but from Java background. Can you explain your code ? – Jess Mar 25 '19 at 21:37
@Jess: very late comment but anyway, my two cents: POSIX `read` expects a line on standard input, reads that and splits it using $IFS contents as a separator, then assigns each chunk to variables given as arguments to `read` (`id` and `string`; `id` getting the first chunk and `string` getting all the remaining chunks). The trick with the two EOFs is called a "heredoc" and AFAIK is the only way to send that string to `read`'s standard input. See also https://pubs.opengroup.org/onlinepubs/9699919799/utilities/read.html. – yassen Oct 12 '21 at 06:56

score 6 · Accepted Answer · answered Nov 12 '13 at 13:48

6

You seem to be using sh to execute the script. Herestrings aren't supported in sh; hence the error.

Ensure that you're using bash to execute the script.

answered Nov 12 '13 at 13:48

devnull

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what is the difference between sh and bash? – clarkk Nov 12 '13 at 13:48
1

@clarkk [Difference between sh and bash](http://stackoverflow.com/questions/5725296/difference-between-sh-and-bash) – Radu Rădeanu Nov 12 '13 at 13:50
1

Some Linux distributions use `dash` (not `bash`) as the shell that implements `sh`. `dash` is (mostly?) limited to the features specified by the POSIX specification, without the extra features like `<<<` implemented by `bash`. – chepner Nov 12 '13 at 13:51
how can I then do this operation with `sh`? – clarkk Nov 12 '13 at 13:52
@clarkk Right; as mentioned in the answer herestrings aren't supported in `sh`. – devnull Nov 12 '13 at 13:58
@clarkk Maybe you could use `cut`. `echo "$s" | cut -d; -f1` would return the first field. – devnull Nov 12 '13 at 14:04
2

this works `echo "$s" | cut -d";" -f1` but how can I assign it into a variable? – clarkk Nov 12 '13 at 14:07
1

@clarkk: Use `var=$(echo "$s" | cut -d";" -f1)` – anishsane Nov 12 '13 at 14:18

score 1 · Answer 3 · answered Aug 18 '18 at 14:19

save it in file split

#!/bin/sh

string=$1
c=0

while [ $c -le $3 ] 
do

val1=`echo "$string" |sed 's/\(^[^'$2']*\)\('$2'\+\)\(.*$\)/\1/'`
string=`echo "$string" |sed 's/\(^[^'$2']*\)\('$2'\+\)\(.*$\)/\3/'`

if [ "$val1" == "$string" ]
then
string=''
fi

if [ "$val1" == "" ]
then
let c=$3
fi

let c=c+1

done

echo $val1

and it work:

root@IPHONE:~# ./split 'a;b;c' ';' 0
a
root@IPHONE:~# ./split 'a/b/c' '\/' 0
a
root@IPHONE:~# ./split 'a/b/c' '\/' 2
c
root@IPHONE:~# ./split 'a/b/c' '\/' 1
b

score 0 · Answer 4 · answered Nov 12 '13 at 14:40

My result:

[root@localhost ~]# bash --version
GNU bash, version 3.2.25(1)-release (i686-redhat-linux-gnu)
Copyright (C) 2005 Free Software Foundation, Inc.
[root@localhost ~]# ./bash
id
[root@localhost ~]# cat bash
s='id;some text here with possible ; inside'
IFS=';' read -r id string <<< "$s"
echo "$id"

Worked here.

score -1 · Answer 5 · answered Nov 12 '13 at 14:34

-1

I have used python2.7 below:

#!/bin/sh

s='id;some text here with possible ; inside'
python -c "ifc, s =';', '$s';print s.split(';')[0] if ifc in s else ''"

Result:

 $ ./test.sh
id

answered Nov 12 '13 at 14:34

Michael Kazarian

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1
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sh - split string by delimiter

code

error

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