Bash: syntax error in expression (error token is ...)

Question

This line in a bash file has been working for six months:

SCRATCH_FOLDER_NAME="${SCRATCH_FOLDER_NAME:scratch--folder}"

and today it decided to be no more, with this error:

SCRATCH_FOLDER_NAME: scratch--folder: syntax error in expression (error token is "folder")

What does it mean?

For reference, here is the complete script:

#!/bin/bash

      SHIMMERCAT_SCRATCH_FOLDER_NAME="${SHIMMERCAT_SCRATCH_FOLDER_NAME:shimmercat-scratch--folder}"
REDIS_UNIX_SOCKET="/unpriv/$SHIMMERCAT_SCRATCH_FOLDER_NAME/redis.sock"

if [[ -z ${DONT_RUN_REDIS+x} ]]; then 

    chown shimmercat:shimmercat $SHIMMERCAT_SCRATCH_FOLDER_NAME

    ...
fi

Maybe try chown shimmercat:shimmercat "$SHIMMERCAT_SCRATCH_FOLDER_NAME" (with the expansion in "")? Which line is the error on? — cxw
– cxw, Commented May 24, 2017 at 15:11
The error is in line 3, the one that I wrote first in the question. — dsign
– dsign, Commented May 24, 2017 at 15:12
I can reproduce the error in both 3.2 and 4.4, when SCRATCH_FOLDER_NAME is set. It's also possible that 4.0 introduced a bug that made it legal, and said bug wasn't fixed until 4.4; I don't have any older installations available to test that theory. — chepner
– chepner, Commented May 24, 2017 at 16:03

Adrian Bartyczak · Accepted Answer · 2017-05-24 15:30:18Z

3

"${SCRATCH_FOLDER_NAME:scratch--folder}" is not a correct parameter expansion. Consider the following, where comma is the delimiter:

# Get string before first matching delimeter
${var%%,*}

# Get string before last matching delimeter
${var%,*}

# Get string after first matching delimeter
${var#*,}

# Get string after last matching delimeter
${var##*,}

As for how it worked I am not sure. Here is a good reference for the different types of parameter expansions.

edited May 24, 2017 at 15:30

answered May 24, 2017 at 15:25

Adrian Bartyczak

2033 silver badges17 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

dsign Over a year ago

Yepp, you are totally right. I should have added a "-", like: SHIMMERCAT_SCRATCH_FOLDER_NAME="${SHIMMERCAT_SCRATCH_FOLDER_NAME:-shimmercat-scratch--folder}" . How it was working before, I have no idea :-(

Collectives™ on Stack Overflow

Bash: syntax error in expression (error token is ...)

1 Answer 1

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related