It works ok as a single tool:
curl "someURL"
curl -o - "someURL"
but it doesn't work in a pipeline:
curl "someURL" | tr -d '\n'
curl -o - "someURL" | tr -d '\n'
it returns:
(23) Failed writing body
What is the problem with piping the cURL output? How to buffer the whole cURL output and then handle it?
This happens when a piped program (e.g. grep) closes the read pipe before the previous program is finished writing the whole page.
In curl "url" | grep -qs foo, as soon as grep has what it wants it will close the read stream from curl. cURL doesn't expect this and emits the "Failed writing body" error.
A workaround is to pipe the stream through an intermediary program that always reads the whole page before feeding it to the next program.
E.g.
curl "url" | tac | tac | grep -qs foo
tac is a simple Unix program that reads the entire input page and reverses the line order (hence we run it twice). Because it has to read the whole input to find the last line, it will not output anything to grep until cURL is finished. Grep will still close the read stream when it has what it's looking for, but it will only affect tac, which doesn't emit an error.
For completeness and future searches:
It's a matter of how cURL manages the buffer, the buffer disables the output stream with the -N option.
Example:
curl -s -N "URL" | grep -q Welcome
Another possibility, if using the -o (output file) option - the destination directory does not exist.
eg. if you have -o /tmp/download/abc.txt and /tmp/download does not exist.
Hence, ensure any required directories are created/exist beforehand, use the --create-dirs option as well as -o if necessary
The server ran out of disk space, in my case.
Check for it with df -k .
I was alerted to the lack of disk space when I tried piping through tac twice, as described in one of the other answers: https://stackoverflow.com/a/28879552/336694. It showed me the error message write error: No space left on device.
You can do this instead of using -o option:
curl [url] > [file]
So it was a problem of encoding. Iconv solves the problem
curl 'http://www.multitran.ru/c/m.exe?CL=1&s=hello&l1=1' | iconv -f windows-1251 | tr -dc '[:print:]' | ...
If you are trying something similar like source <( curl -sS $url ) and getting the (23) Failed writing body error, it is because sourcing a process substitution doesn't work in bash 3.2 (the default for macOS).
Instead, you can use this workaround.
source /dev/stdin <<<"$( curl -sS $url )"
Trying the command with sudo worked for me. For example:
sudo curl -O -k 'https url here'
note: -O (this is capital o, not zero) & -k for https url.
I had the same error but from different reason. In my case I had (tmpfs) partition with only 1GB space and I was downloading big file which finally filled all memory on that partition and I got the same error as you.
I encountered the same problem when doing:
curl -L https://packagecloud.io/golang-migrate/migrate/gpgkey | apt-key add -
The above query needs to be executed using root privileges.
Writing it in following way solved the issue for me:
curl -L https://packagecloud.io/golang-migrate/migrate/gpgkey | sudo apt-key add -
If you write sudo before curl, you will get the Failed writing body error.
For me, it was permission issue. Docker run is called with a user profile but root is the user inside the container. The solution was to make curl write to /tmp since that has write permission for all users , not just root.
I used the -o option.
-o /tmp/file_to_download
In my case, I was doing:
curl <blabla> | jq | grep <blibli>
With jq . it worked: curl <blabla> | jq . | grep <blibli>
I encountered this error message while trying to install varnish cache on ubuntu. The google search landed me here for the error (23) Failed writing body, hence posting a solution that worked for me.
The bug is encountered while running the command as root curl -L https://packagecloud.io/varnishcache/varnish5/gpgkey | apt-key add -
the solution is to run apt-key add as non root
curl -L https://packagecloud.io/varnishcache/varnish5/gpgkey | apt-key add -
The explanation here by #Kaworu is great: https://stackoverflow.com/a/28879552/198219
This happens when a piped program (e.g. grep) closes the read pipe before the previous program is finished writing the whole page. cURL doesn't expect this and emits the "Failed writing body" error.
A workaround is to pipe the stream through an intermediary program that always reads the whole page before feeding it to the next program.
I believe the more correct implementation would be to use sponge, as already suggested by #nisetama in the comments:
curl "url" | sponge | grep -qs foo
I got this error trying to use jq when I didn't have jq installed. So... make sure jq is installed if you're trying to use it.
In Bash and zsh (and perhaps other shells), you can use process substitution (Bash/zsh) to create a file on the fly, and then use that as input to the next process in the pipeline chain.
For example, I was trying to parse JSON output from cURL using jq and less, but was getting the Failed writing body error.
# Note: this does NOT work
curl https://gitlab.com/api/v4/projects/ | jq | less
When I rewrote it using process substitution, it worked!
# this works!
jq "" <(curl https://gitlab.com/api/v4/projects/) | less
Note: jq uses its 2nd argument to specify an input file
Bonus: If you're using jq like me and want to keep the colorized output in less, use the following command line instead:
jq -C "" <(curl https://gitlab.com/api/v4/projects/) | less -r
(Thanks to Kowaru for their explanation of why Failed writing body was occurring. However, their solution of using tac twice didn't work for me. I also wanted to find a solution that would scale better for large files and tries to avoid the other issues noted as comments to that answer.)
I was getting curl: (23) Failed writing body . Later I noticed that I did not had sufficient space for downloading an rpm package via curl and thats the reason I was getting issue. I freed up some space and issue for resolved.
I had the same question because of my own typo mistake:
# fails because of reasons mentioned above
curl -I -fail https://www.google.com | echo $?
curl: (23) Failed writing body
# success
curl -I -fail https://www.google.com || echo $?
I added flag -s and it did the job. eg: curl -o- -s https://raw.githubusercontent.com/nvm-sh/nvm/v0.39.1/install.sh | bash
I am writing a shell script where i want to ssh to a server and get the cpu and memory details data of that displayed as a result. I’m using the help of top command here.
Script line:
ssh -q user#host -n “cd; top -n 1 | egrep ‘Cpu|Mem|Swap’”
But the result is
TERM environment variable is not set.
I had checked the same in the server by entering set | grep TERM and got result as TERM=xterm
Please someone help me on this. Many thanks.
Try using the top -b flag:
ssh -q user#host -n "cd; top -bn 1 | egrep 'Cpu|Mem|Swap'"
This tells top to run non-interactively, and is intended for this sort of use.
top need an environment. You have to add the parameter -t to get the result:
ssh -t user#host -n "top -n 1 | egrep 'Cpu|Mem|Swap'"
Got it..!! Need to make a small modification for the below script line.
ssh -t user#host -n "top -n 1 | egrep 'Cpu|Mem|Swap'"
Instead of -t we need to give -tt. It worked for me.
To execute command top after ssh’ing. It requires a tty to run. Using -tt it will enable a force pseudo-tty allocation.
Thanks stony for providing me a close enough answer!! :)
I'm having an issue with a simple script here. Just can't find documented help that resolves my issue.
Here is my script.
#!/bin/bash
$VCOPS_BASE/cassandra/apache-cassandra-2.1.8/bin/cqlsh --ssl --cqlshrc $VCOPS_BASE/user/conf/cassandra/cqlshrc
-e "cql_statement;"
I left out the cql for simplicity's sake, but everytime I run my file from the command line I simply enter the cql shell.
--execute and echo don't work either and I'm really not sure why I would need to save the cql statement to another file.
Any help would be appreciated.
That's because -e is a cqlsh option, not a bash command that stands on its own. Therefore, it needs to be on the same line as your cqlsh command.
#!/bin/bash
$VCOPS_BASE/cassandra/apache-cassandra-2.1.8/bin/cqlsh --ssl --cqlshrc $VCOPS_BASE/user/conf/cassandra/cqlshrc -e "cql_statement;"
I tested this out with a simpler version:
aploetz#dockingBay94:~/scripts$ cat getEmail.sh
#!/bin/bash
cqlsh -u cassandra -p cassandra -e "SELECT * FROm stackoverflow.users_by_email WHERe email='mreynolds#serenity.com';"
aploetz#dockingBay94:~/scripts$ ./getEmail.sh
email | id | username
------------------------+--------------------------------------+----------
mreynolds#serenity.com | d8e57eb4-c837-4bd7-9fd7-855497861faf | Mal
(1 rows)
aploetz#dockingBay94:~/scripts$
Hello to professionals !
There was a good and simplest script idea to make mysqldump of every database - taken from
dump all mysql tables into separate files automagically?
author - https://stackoverflow.com/users/1274838/elias-torres-arroyo
with script as follows
#!/bin/bash
# Optional variables for a backup script
MYSQL_USER="root"
MYSQL_PASS="PASSWORD"
BACKUP_DIR="/backup/01sql/";
# Get the database list, exclude information_schema
for db in $(mysql -B -s -u $MYSQL_USER --password=$MYSQL_PASS -e 'show databases' | grep -v information_schema)
do
# dump each database in a separate file
mysqldump -u $MYSQL_USER --password=$MYSQL_PASS "$db" | gzip > "$BACKUP_DIR/$db.sql.gz"
done
sh
but the problem is that this script does not "understand" arguments like
--add-drop-database
to perform
mysqldump -u $MYSQL_USER --password=$MYSQL_PASS "$db" --add-drop-database | gzip > "$BACKUP_DIR/$db.sql.gz"
Is there any idea how to force this script to understand the additional arguments listed under
mysqldump --help
because while all my tests shows it doesn't.
Thank you in advance for any hint to try !
--add-drop-database works only with --all-databases or --databases.
See please the reference in docs
So in your case mysqldump utility ignore mentioned parameter because you are going to dump one database.
I would like to count the occurrence of word ERROR by using command:-
mysql -B -u root -pxxxx -h abc -e show databases | grep -c "ERROR"
However my understanding says it should return 1 however it is returning it as O
Why ?
Also please let me know the significance of mysql -B and -e
Thanks,
Ruchir
Errors go to the standard error (stderr) by default, so you need to redirect it to standard output (via 2>&1). In which case grep can process them:
mysql -B -u root -pxxxx -h abc -e show databases 2>&1 | grep -c "ERROR"