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Is there a way to 'uniq' by column?
...first of an equal run." So, it is indeed "the first occurrence of the duplicate before sorting."
– Geremia
Apr 15 '16 at 17:32
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While loop to test if a file exists in bash
...ve my solution for anyone who experiences the same.
I found that if I ran cat /tmp/list.txt the file would be empty, even though I was certain that there were contents being placed immediately in the file. Turns out if I put a sleep 1; just before the cat /tmp/list.txt it worked as expected. There ...
Output to the same line overwriting previous output?
I am writing an FTP downloader. Part of to the code is something like this:
8 Answers
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Using multiple delimiters in awk
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awk -F'[/=]' '{print $3 "\t" $5 "\t" $8}' file
Produces:
tc0001 tomcat7.1 demo.example.com
tc0001 tomcat7.2 quest.example.com
tc0001 tomcat7.5 www.example.com
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impro...
AWK: Access captured group from line pattern
...rint ary['${2:-'0'}']}'; }
Usage
Capture regex for each line in file
$ cat filename | regex '.*'
Capture 1st regex capture group for each line in file
$ cat filename | regex '(.*)' 1
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Exception handling in R [closed]
...iscontinued, but you can try
Github search as e.g. in this query for tryCatch in language=R;
Ohloh/Blackduck Code search eg this query for tryCatch in R files
the Debian code search engine on top of the whole Debian archive
Just for the record, there is also try but tryCatch may be preferable....
echo that outputs to stderr
...t, including arguments (-n) that echo would normally swallow:
echoerr() { cat <<< "$@" 1>&2; }
Glenn Jackman's solution also avoids the argument swallowing problem:
echoerr() { printf "%s\n" "$*" >&2; }
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Get Android .apk file VersionName or VersionCode WITHOUT installing apk
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how can I read apk content without installing the application? @PatrickCho
– talha06
Feb 22 '14 at 14:27
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How update the _id of one MongoDB Document?
...store the document in a variable
doc = db.clients.findOne({_id: ObjectId("4cc45467c55f4d2d2a000002")})
// set a new _id on the document
doc._id = ObjectId("4c8a331bda76c559ef000004")
// insert the document, using the new _id
db.clients.insert(doc)
// remove the document with the old _id
db.client...
How to get a specific version of a file in Mercurial?
...ace to match a prior revision. If you want it not in place you can use hg cat -r revisionid filename (substituting revisionid and filename of course) which will output the file to stdout, suitable for redirecting anyplace you'd like.
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