During test of a file, binary operator expected error

Masoom · 08-10-2015, 07:04 AM

Hi,
To remove some files automatically, I made a script but during Test the binary operator expected Error is being raised. Here is a piece of code from where error generating
---------------

Code:

if test -f Fri*.* ; then
printf "Friday files are existing and going to be removed \n"
rm Fri*.*
fi

-----------------------------
Error is on the first line, Here a point is to be noted if I test one file then there is no error for example if I write the first line like

Code:

if test -f FriDB.tar.gz ; then
printf "Friday files are existing and going to be removed \n"
rm Fri*.*
fi

Discussion regarding the same error has been done on this same forum but unfortunately I failed to follow them.
Regards.

schneidz · 08-10-2015, 08:48 AM

what error are you getting ?

https://lmddgtfy.net/?q=linux%20test...ltiple%20files

rknichols · 08-10-2015, 09:42 AM

Quote:

Originally Posted by Masoom

Here is a piece of code from where error generating
---------------

Code:

if test -f Fri*.* ; then
printf "Friday files are existing and going to be removed \n"
rm Fri*.*
fi

That fails because the filename expansion results in multiple words being inserted in the test command. It will look like

Code:

test -f FriDB.tar.gz FriFile2.xx FriFile3.yy FriFile4.zz

The test command has no idea what to do with the rest of those arguments.

There are many ways to accomplish what you are trying to do. My own favorite is to store the result of the expansion in an array, then test the first element of the array.

Code:

declare -a Files
Files=(Fri*.*)
if [ "${Files[0]}" != "Fri*.*" ]; then
    printf "Friday files are existing and going to be removed \n"
    rm -f "${Files[@]}"
fi

Or, an alternative using nullglob to avoid repeating the pattern:

Code:

shopt -s nullglob
declare -a Files
Files=(Fri*.*)
if [ ${#Files[*]} -gt 0 ]; then
    printf "Friday files are existing and going to be removed \n"
    rm -f "${Files[@]}"
fi

Note: I've used "[ ... ]" in place of the test command. That is strictly a matter of preference. The two constructs are identical.

Masoom · 08-10-2015, 10:05 AM

Hi,
Thanks schneidz & rknichols, Suppose I have two files which begins with "FriXXX" letters, I wanted that rm command should be run when both files exist, so I try with your provided solutions, can you explain it more using array I am feeling it easy to understand.
Regards.

Masoom · 08-10-2015, 10:06 AM

Hi,
Thanks schneidz & rknichols, Suppose I have two files which begins with "FriXXX" letters, I wanted that rm command should be run when both files exist, so I try with your provided solutions, can you explain it more using array I am feeling it easy to understand.
Regards.

schneidz · 08-10-2015, 10:16 AM

i think you will need to get creative like so:

Code:

declare -a Files
Files=(Fri*.*)
if [ ${#Files[@]} -eq 2 ]
then
    printf "Friday files are existing and going to be removed \n"
    rm -f "${Files[@]}"
fi

grail · 08-10-2015, 10:22 AM

Or if you want to use just basics, use a for loop with your test inside it

rknichols · 08-10-2015, 11:21 AM

Quote:

Originally Posted by Masoom

Hi,
Thanks schneidz & rknichols, Suppose I have two files which begins with "FriXXX" letters, I wanted that rm command should be run when both files exist, so I try with your provided solutions, can you explain it more using array I am feeling it easy to understand.
Regards.

The answer depends on whether you need to test for:

Two specific files, and there should be no other files that match the pattern,
Two specific files, and there could be others that match the pattern,
At least two files match the pattern, but there could be others,
Any two files that match the pattern, and there should be exactly two.

Somehow I don't feel like offering code for each of those cases. The suggestion from schneidz above should cover case 4. Which one seems to be of concern to you.

Masoom · 08-12-2015, 01:35 AM

Thanks to all that try to expand my logic in scripting but I got my point through the following
FriFiles=$(ls Fri*.* | wc -l)
if test "$FriFiles" -ge 2 ; then
rm Fri*.*
fi
Regards.

zhjim · 08-12-2015, 05:16 AM

Why not use find command. You can even delete things.

Quote:

find /your/log/file/path -iname "Fri*" -delete -depth 0

-iname is incase sensitive search
-delete deletes
-depth 0 takes care that only files in the given directory are affected and non in lower subdirs.

rknichols · 08-12-2015, 09:20 AM

Quote:

Originally Posted by zhjim

Why not use find command. You can even delete things.

It's a bit difficult to require that two matching file be present and to get the message printed, and printed just once.

zhjim · 08-13-2015, 03:40 AM

That requirement is not that hard. And I doubt that it really is needed if I read the starting post. I guess that he just wants to delete all files with Fri in their name. Be it 1, two or a 100 thousand.

pan64 · 08-13-2015, 03:44 AM

what about:

Code:

rm Fri*

??