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0
votes
1answer
27 views

What does ESRCH mean?

Out of: http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/errno.h.html It's always pretty clear why an errno code is named a particular way except for this one. How does SRCH relate to No such ...
2
votes
1answer
24 views

Error exit script from within command substitution

If I have a function: myfunction() { [ -d somedirectory ] && [ "some other condition" ] || { echo "error" >&2 ; exit 1; } global_var=somevalue } And I call it from within another ...
18
votes
6answers
1k views

How can I suppress output only if the command succeeds?

I would like to simplify the output of a script by suppressing the output of secondary commands that are usually successful. However, using -q on them hides the output when they occasionally fail, so ...
1
vote
1answer
92 views

Bash script to select files to zip/unzip

I'm trying to zip and unzip files with a bash script, but I'm new and I have problems. I will explain what the script currently does, and then what I wanted it to do. User selects “compress”: a file ...
2
votes
1answer
23 views

how to differentiate error returned while reading and for EOF in shell script

I have this task of uploading a delimited file and processing it. Once the processing is done, i either say its successful and if parsing fails, i need to throw the error. I'm reading this file line ...
0
votes
0answers
11 views

Labeling error messages

When dealing with errors, utilities often print their name followed by the error message, for example, sed, cat, awk, etc. sed: foo: No such file or directory Others print the word fatal, followed ...
0
votes
2answers
227 views

Debian live iwlwifi firmware error

When booting Debian live onto my computer, I encountered the errors: [ 19.456064] iwlwifi 0000:03:00.0: firmware: failed to load iwlwifi-7265-9.ucode (-2) [ 19.456183] iwlwifi 0000:03:00.0: ...
1
vote
2answers
126 views

What's the most efficient way to log crontab shell script errors with error occurred time?

A common way to log crontab task errors looks like below: 1 */8 * * * sh /pseudo_path/test.sh 2>> my_err_log It's a concise command, but it can't record the error occurred time, and the path ...
3
votes
2answers
97 views

Simultaneously check for empty output and successful exit status

I'd like to write the following test in an installer script1: if [ -n "`/etc/grub.d/30_os-prober`" ]; then install_dual_boot else install_linux_only fi However, it's also possible that ...
0
votes
2answers
4k views

apt-get update failed to fetch and /sources.list.d/ empty

Running the sudo apt-get update command, I got the following error: Fetched 988 kB in 16s (59,3 kB/s) W: Failed to fetch ...
0
votes
1answer
27 views

Warning message after updating

I have Linux Mint 17 Cinnamon edition and after updating using the terminal: sudo apt-get && sudo apt-get upgrade I got this warning message: ... Building dependency tree Reading ...
1
vote
2answers
525 views

Capture errors in a SFTP script

I have a sub sh file which puts receives an input of local directory and path to the remote directory and sends the file to the remote directory. If the remote path is invalid the error cannot be ...
1
vote
1answer
40 views

Print nth pipeline command in bash

In bash, the PIPESTATUS array holds the return values of commands in a pipeline. Suppose that in the pipeline cmd1 | cmd2 | cmd3, the second command returns an error. Checking PIPESTATUS gives the ...
1
vote
1answer
889 views

Shell script `rm -r`: Redirect write-protected prompt and answer “n”

I have a few lines in a shell script whose function is to iterate through directories, match some names, and delete them. Some areas of the file system are write protected and I would like to leave ...
-1
votes
2answers
230 views

Why to set errno to zero at the time of initialization of the program and can't test it before error occurred? [closed]

I am reading the material available on errno variable of <errno.h> header file. I read : " A value of 0 indicates that there is no error in the program." and "As a good practice, developer ...
1
vote
0answers
751 views

Repeated error : #error “Only <glib.h> can be included directly.”

I have a research on author attribution compression distance. And I should use "Complearn" ,which is a compression program, in my work. But in the beginning I have problem in installing this program. ...
1
vote
1answer
403 views

open() return new file descriptor posix [closed]

I have to set the return values for open() in posix. How do I return "the new file descriptor" as it is said in the Linux man pages: RETURN VALUE open(), openat(), and creat() return the new ...
2
votes
1answer
680 views

How to get non-zero exit code from Puppet when configuration cannot be applied?

I've tried the following Puppet configuration to disable the root password: class users { user { 'root': password => '*', } } But after applying it with no warnings or error messages I ...
2
votes
4answers
365 views

Mute system error message in a script file and display mine

I have created a simple script to move all the files with .sh suffix in the current working directory to a designated directory If there was no such file, the script should output only an error ...
3
votes
1answer
235 views

How to make dd fail if it invalid skip value is specified?

When I invoke dd with an invalid value for skip it prints an error message and does nothing, but doesn't return with a value different from 0, e.g. $ cd /tmp $ mkdir xy $ cd xy $ truncate -s 2M ...
4
votes
2answers
193 views

Shell script error handling while assigning STDOUT to variable

I am trying to implement error handling in my shell script as described in the 2nd answer in Best practice to use $? in bash? My script looks like this: #!/bin/bash try() { "$@" code=$? ...
1
vote
1answer
337 views

TCL script try catch

I have a TCL script that sets a number of variables and reads several files. The last file it reads may contain sensitive information, so I need to make sure this file gets deleted even if an error ...
4
votes
3answers
439 views

why bash increment: `n=0;((n++));` return error? [duplicate]

n=0; ((n++));echo "ret=$?;n=$n;" ((n++));echo "ret=$?;n=$n;" ((n++));echo "ret=$?;n=$n;" from n=1 on, ((n++)) works correctly, only when n=0, ((n++)) return error, and I am using a trap '' ERR that ...
3
votes
1answer
223 views

Errtrace and local

I am using the following script: #!/bin/bash -Eu trap 'echo Hi' ERR exit_failure() { echo "Hello, World!" return 1 } sub_failure() { res=$(exit_failure) } sub_failure It results in the ...
3
votes
2answers
319 views

bash 'nounset' on sub-shell/child doesn't force main script to exit, how to workaround that globally?

With this script: tstNounset.sh #!/bin/bash set -x set -o nounset;set -u echo `echo $str` function FUNC1() { echo $str; };export -f FUNC1;bash -c FUNC1 function FUNC2() { set -u;echo $str; };export ...
0
votes
1answer
297 views

Using trap with ERR: How do I send $?

In bash 4.x If I have: err_handler() { echo You received error $1|mail -s "script error" MAILTO } trap err_handler ERR how do I send the actual stderr output to the function when the trap is ...
8
votes
3answers
433 views

How do I capture the exit code / handle errors correctly when using process substitution?

I have a script that parses file names into an array using the following method taken from a Q&A on SO: unset ARGS ARGID="1" while IFS= read -r -d $'\0' FILE; do ARGS[ARGID++]="$FILE" done ...
3
votes
1answer
531 views

Strange error (?) when I run `man` command from a folder that no longer exists

Let's have a look at the followings: radu@Radu:~$ mkdir test radu@Radu:~$ cd test radu@Radu:~/test$ rmdir ~/test radu@Radu:~/test$ man ls man: can't change directory to '': No such file or directory ...
5
votes
2answers
12k views

How to check whether a command such as curl completed without error?

I am using curl to upload a file to a server via an HTTP post. curl -X POST -d@myfile.txt server-URL When I manually execute this command on the command line, I get a response from the server like ...
7
votes
2answers
562 views

Making sure a command has executed in bash

I have a bash file with commands to merge pcap files. I want to know if there is anyway to make sure a line in bash runs or not. Like in windows bat file we have %ErrorLevel% ¨ Say a command touch -r ...
10
votes
3answers
5k views

chmod + silent mode + how force exit code 0 in spite of error

Is it possible execute chmod and ignore error from command Example ( remark file.txt not exsist to show the example ) When I type chmod 777 file.txt I get error on the output chmod: cannot ...
5
votes
2answers
579 views

How to implement logwatch functionality on top of systemd journal?

Logwatch scans logfiles with regular intervals, collects errors and stuff, then mails it to the admin. This was back in syslog and logfiles days. What's the corresponding solution for systemd's ...
2
votes
1answer
427 views

How to have a bash script perform a specific action on errors of _each_ command?

Similarly to set -e performs an exit on "uncaught" $? != 0, I'd like to have this event trigger the execution of another command, e.g. a logger call. How can this be done?
5
votes
2answers
2k views

How does Linux md-RAID handle disk read errors?

There are 2 cases: the read command times out at kernel level (30 seconds by default), the drive reports its unability to read a given sector before the kernel lose patience (the case I'm ...
5
votes
1answer
878 views

Bash capture any error like -e but don't exit, do something else

I want to set a flag in a shell script (bash) so that if anything returns non-zero, a flag is set (i.e. set a variable like errors="True"). So far, I've thought of calling the script with ...
1
vote
1answer
419 views

Unwanted messages every time I attempt to login?

I am using Linux Mint Olivia and it worked fine for past couple of months but from yesterday it keep showing these message whenever I want to login to my PC: Keys: Press S to skip mounting or M for ...
2
votes
2answers
87 views

Different error messages when using different strings in terminal

When I insert, for example, unix.stackexchange.com followed by Enter in terminal, I get the following error: unix.stackexchange.com: command not found This is ok and as I expected. But when I insert ...
5
votes
5answers
17k views

How to catch an error in a linux bash script?

I made the following script: # !/bin/bash # OUTPUT-COLORING red='\e[0;31m' green='\e[0;32m' NC='\e[0m' # No Color # FUNCTIONS # directoryExists - Does the directory exist? function directoryExists ...
3
votes
2answers
470 views

Getting the complete command line that caused an ERR , while trap

How do I make trap to return the command that caused an ERR? $function err_handler() { echo "$0 caused the error"; } $ trap err_handler ERR $ grep -ci "failed" test4 &>/dev/null -bash caused ...
1
vote
1answer
199 views

Detecting SSH timeout

Is there any way I could trigger a bash script when ssh times out? I have an alias to set the tmux title when starting ssh. The alias also includes a title change after the ssh session, which works ...
2
votes
3answers
603 views

Exception handling when using tail -f to monitor a log

I have a main script calling the script to do the monitoring. I am trying to catch the exception that the log is missing or not accessible anymore. tail -f is used instead of -F since the logs are ...
14
votes
4answers
5k views

How to make bash abort the execution of a script on syntax error?

To be on safe side, I'd like bash abort the execution of a script if it encounters a syntax error. To my surprise, I can't achieve this. (set -e is not enough.) Example: #!/bin/bash # Do exit on ...
7
votes
4answers
348 views

Which data should be excluded from log files , error messages etc. if posted online?

What data should one erase from log files, error messages etc., if posting them as a screenshot so as not to expose sensitive information? As I have little knowledge about this topic, I can vividly ...
9
votes
1answer
1k views

rsync: skip files for which I don't have permissions

I'm using rsync -rlptD to copy a directory from another user. There are a few files (I have no way of knowing these in advance) which I don't have permission to copy. Is there a way have rsync ignore ...
4
votes
3answers
346 views

Mail cron output only when Git throws a real error

There exists a Git repo that is on one server, we want to generate doxygen output for it on a different server. The following command works for me but has the downside of sending a mail everytime the ...
3
votes
5answers
4k views

Suppress server message in rsync

When I rsync or scp from a particular server I get a rather long message telling me the rules of the server. However when I setup regular pulls, I'd like to be able to suppress those messages in my ...
3
votes
1answer
1k views

Capture screen content for error parsing

I am a database administrator working with DB2 on AIX. (Please continue to read as this is related more to ksh than DB2, otherwise I would have posted this over on dba.stackexchange.com.) I am ...
3
votes
2answers
21k views

how to view php and server error logs?

I am getting the WSOD now since editing settings.php; php.ini and .htaccess trying to update my site and I need to see error logs to find out what is happening. Also how do you clear cache in command ...
3
votes
1answer
2k views

What does “DMA: Out of SW-IOMMU space” error mean?

First the link: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1060268 Since this affects the kernel and other Distros, what does this type of error mean and why it happens?
1
vote
0answers
592 views

error: implicit declaration of function ‘rt_dev_socket’

The developer says: http://comments.gmane.org/gmane.linux.real-time.rtnet.user/2546 Now how can I tell the Makefile to look for headers in /usr/local/rtnet/include respectively ...