I searched man cp, but can find no quiet option, so that cp does not report "No such file or directory".
How can I make cp not print this error if it attempts, but fails, to copy the file?
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6 Answers
Well everyone has suggested that redirecting to /dev/null would prevent you from seeing the error, but here is another way. Test if the file exists and if it does, execute the cp command.
[[ -e f.txt ]] && cp f.txt ff.txt In this case, if the first test fails, then cp will never run and hence no error.
8 Comments
nneonneo
However,
cp may still throw other kinds of errors in this case, e.g. access denied. (It is a great solution if you want to suppress only not-found errors).
rici
@nneonneo: ... aside from the race condition
nneonneo
@rici: yeah, yeah, there's a race condition. It's also still possible for it to report not-found if the destination doesn't exist. It isn't foolproof, but it is better if you only want to suppress one kind of error.
jaypal singh
Thanks guys, valid points! Have up-voted so that OP gets a look at it before deciding on the answer.
rici
@tc88: another process could delete the file, which might take place between the test and the action. On Unix, it is not a problem if the file is deleted during the copy, because the file's contents are not removed as long as the file is in use, so the "test before using" idiom creates a race condition. This is a common mistake. See en.m.wikipedia.org/wiki/Time_of_check_to_time_of_use
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If you want to suppress just the error messages:
cp original.txt copy.txt 2>/dev/null If you want to suppress bot the error messages and the exit code use:
cp original.txt copy.txt 2>/dev/null || : 
2 Comments
Szczepan Hołyszewski
Can you explain the colon at the end?
paoloose
The
: command is a shell builtin equivalent to the true command, a no-op that just returns success, i.e., returns 0. In this context it basically says "execute the copy, or, if fails, execute :", wich always succeed, making the whole command always succeed.The general solution is to redirect stderr to the bit bucket:
cp old_file new_file 2>>/dev/null Doing so will hide any bugs in your script, which means that it will silently fail in various circumstances. I use >> rather than > in the redirect in case it's necessary to use a log file instead.
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rsync -avzh --ignore-missing-args /path/to/source /path/to/destination ignore-missing-args: errors ignored are those related to source files not existing
Like for any error printed to STDERR, just redirect it to /dev/null:
cp a b 2> /dev/null 
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Redirect:
cp ... 2>/dev/null 