On 21 May 2023 at 16:05, Go Canes wrote:
From: Go Canes <letsgonhlcanes0(a)gmail.com>
Date sent: Sun, 21 May 2023 16:05:06 -0400
Subject: Re: Strange error running scripts. without
#!/usr/bin/bash
To: mikes(a)guam.net,
Community support for Fedora users
<users(a)lists.fedoraproject.org>
On Sat, May 20, 2023 at 10:18 PM Michael D. Setzer II
<msetzerii(a)gmail.com> wrote:
> Recently was getting a strange error when running a script that didn't have
#!/usr/bin/bash at top?
> free(): invalid next size (fast)
> Aborted (core dumped)
> Just adding the line fixes the issue, but not sure why??
> Have run the script before with no such error, but had been a while? Script was
just one line? Now 2 lines.
> #!/usr/bin/bash
> boincmgr -e /home/msetzerii/BOINC -d /home/msetzerii/BOINC
I understand that adding the shebang makes it likely that this was
something to do with the script, but was wondering if somehow the
"free" error was actually coming from boincmgr.
Also, any chance in the past you invoked it as "sh script.sh" as
opposed to "./script.sh"? And now you are just doing "./script.sh"?
That would explain the change in behavior.
Located the earlier script. It still gave the error so tried
strace and got
strace ./mktext2x.sh
execve("./mktext2x.sh", ["./mktext2x.sh"],
0x7ffc37e55570 /* 35 vars */) = -1 ENOEXEC (Exec
format error)
strace: exec: Exec format error
+++ exited with 1 +++
But running the corrected one ran fine as is and with
strace.
But then tried to run it again, and mktext2x.sh runs
without error?
Running the one with bash line, strace works fine.
strace ./mktext2.sh
execve("./mktext2.sh", ["./mktext2.sh"], 0x7ffc9afbcb80
/* 63 vars */) = 0
brk(NULL) = 0x55a016794000
The script is:
#!/usr/bin/bash
for a in $(ls -1rt status_cgi*); do
n=$(echo "$a" | sed 's/status_cgi.//g;s/status_cgi//g');
html2text -b0 "$a" >text."$n" ;
grep "^Downstream" <text."$n" | sed 's/[[:alpha:]|]//g;s/^
//g;s/ / /g' | cut -f1,4,5,9 -d' ' >down."$n" ;
done
So, why it seems to always work with the #! line,
but seems to randomly work without it?
But always fails with strace without #! line?
Extracting cable modem status info for many saved
status_cgi files.
Strange that it isn't consistant?
+------------------------------------------------------------+
Michael D. Setzer II - Computer Science Instructor
(Retired)
mailto:mikes@guam.net
mailto:msetzerii@gmail.com
Guam - Where America's Day Begins
G4L Disk Imaging Project maintainer
http://sourceforge.net/projects/g4l/
+------------------------------------------------------------+