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Commands using tr from sorted by
Terminal - Commands using tr - 282 results
tr -dc '[:print:]' < <file>
2012-11-22 06:29:26
User: seb1245
Functions: tr
Tags: printing tr
3

tr has some predefined sets of characters that are more convenient to use than characters codes

cat /dev/urandom | tr -dc 'a-zA-Z0-9' | fold -w 18 | head -1 | python -c "import sys,crypt; stdin=sys.stdin.readline().rstrip('\n'); print stdin;print crypt.crypt(stdin)"
2012-11-09 00:40:22
User: cnyg
Functions: cat fold head python tr
1

Generate a 18 character password from character set a-zA-Z0-9 from /dev/urandom, pipe the output to Python which prints the password on standard out and in crypt sha512 form.

tr -d '\r' < <input> > <output>
echo "your string here" | tr '\!-~' 'P-~\!-O'
2012-11-06 12:49:00
User: DevEd
Functions: echo tr
1

This command will encode a string using the ROT47 cipher.

java -jar app.jar -cp $(echo lib/*.jar | tr ' ' ':')
2012-10-29 12:51:46
User: xymor
Functions: echo tr
Tags: java cli
0

Lauching an app including jars in an adjacent lib folder to its classpath

tr -dc '[:graph:]' </dev/urandom | head -c30; echo
head -c7 /dev/urandom|base64|tr -d '='
tr -dc A-Za-z0-9_ < /dev/urandom | head -c 10 | xargs
echo $(</dev/urandom tr -dc 1-6 | head -c1)
echo $(find <directory> -name '*.<extension>' -exec du -s {} \; | tee $(tty) | cut -f1 | tr '\n' '+') 0 | bc
2012-09-17 22:46:50
User: ysangkok
Functions: cut du echo find tee tr
-1

Also shows files as they are found. Only works from a tty.

tcpdump -ntr NAME_OF_CAPTURED_FILE.pcap 'tcp[13] = 0x02 and dst port 80' | awk '{print $4}' | tr . ' ' | awk '{print $1"."$2"."$3"."$4}' | sort | uniq -c | awk ' {print $2 "\t" $1 }'
lsof -p `pidof pidgin` | awk '{ print $9 }'|egrep `hostname` | grep -o ">[^:]\+:" | tr -d ":>" | while read line; do host $line; done;
pbpaste | tr '\r\n' '\n' | tr '\r' '\n' | pbcopy
2012-07-31 10:50:14
User: adambrenecki
Functions: tr
0

Copying and pasting from Office documents open in Office:mac can dirty your files with Windows CRLF and (inexplicably) Classic Mac OS LF newlines, which can break some tools. This snippet replaces them with good ol' Unix LF newlines.

export PATH= $(echo $PATH | tr ':' '\n' | awk '!/matching string/' | paste -sd:)
ssh-keygen -l -f [pubkey] | cut -d ' ' -f 2 | tr -ds '\n:' ''
tr -s ' '
2012-06-26 19:34:18
User: ankush108
Functions: tr
Tags: tr
0

Convert long list of ' ' to a single space. Compress space and other characters.

tr a-z A-Z < file.txt
for file in * ; do mv "$file" `echo "$file" | tr ' ' '_' | tr '[A-Z]' '[a-z]'`; done
2012-05-06 17:54:06
User: cengztr
Functions: file mv tr
0

All files in the directory will be renamed replacing every space in the filename by "_" (underline) and converting upper case characters to lower case characters.

e.g. Foo Bar.txt --> foo_bar.txt

printf "%$(tput cols)s\n"|tr ' ' '='
2012-04-21 23:26:55
Functions: printf tr
9

Use tput cols to find the width of the terminal and set it as the minimum field width.

dd if=/dev/zero bs=64K count=1 | tr "\0" "\377" > all_ones
2012-04-17 18:01:59
User: anduril462
Functions: dd tr
1

dd can be used with /dev/zero to easily create a file of all zero-bytes. Pipe that through tr and use octal conversions to change the byte values from zero to 0xff (octal 0377). You can replace 0377 with the byte of your choice. You can also use \\0 and \\377 instead of the quoted version.

cal | egrep -e '^ [0-9]|^[0-9]' | tr '\n' ' ' | awk '{print $NF}'
2012-04-16 11:58:09
User: gouverney
Functions: awk cal egrep tr
0

Returns last day of current month. Useful to implement a bash script backup based on a GFS strategy.

paste <(seq 7 | shuf | tr 1-7 A-G) <(seq 7 | shuf) | while read i j; do play -qn synth 1 pluck $i synth 1 pluck mix $2; done
dng(){ local a;a=$(sed '/'"$1"'/!d' /etc/hosts |sed '=;'"${2-1,$}"'!d'|sed '/ /!d');echo $a|tr '\040' '\n'|nl -bp'[0-9]$'|less -E;export dn=$(echo $a|sed 's,.* ,,');export ip=$(echo $a|sed 's, .*,,');echo \$dn=$dn;echo \$ip=$ip;}
2012-04-01 23:57:09
User: argv
Functions: echo export less nl sed tr
0

usage: dng BRE [selection]

default selection is the last match

DNS is ok, but although domainnames may be easier to remember than IP numbers, it still requires typing them out. This can be error-prone. Even more so than typing IPv4 numbers, depending on the domainname, its length and complexity.

find /some/path -type f -and -iregex '.*\.mp3$' -and -print0 | tr -d -c '\000' |wc -c
2012-03-31 21:57:33
User: kyle0r
Functions: find tr wc
1

In this example, the command will recursively find files (-type f) under /some/path, where the path ends in .mp3, case insensitive (-iregex).

It will then output a single line of output (-print0), with results terminated by a the null character (octal 000). Suitable for piping to xargs -0. This type of output avoids issues with garbage in paths, like unclosed quotes.

The tr command then strips away everything but the null chars, finally piping to wc -c, to get a character count.

I have found this very useful, to verify one is getting the right number of before you actually process the results through xargs or similar. Yes, one can issue the find without the -print0 and use wc -l, however if you want to be 1000% sure your find command is giving you the expected number of results, this is a simple way to check.

The approach can be made in to a function and then included in .bashrc or similar. e.g.

count_chars() { tr -d -c "$1" | wc -c; }

In this form it provides a versatile character counter of text streams :)

scanelf --nobanner --recursive --quiet --needed --format "+n#F" $1 | tr ',' '\n' | sort -u
2012-03-29 18:30:45
User: Flameeyes
Functions: sort tr
1

This works in combination with http://www.commandlinefu.com/commands/view/10496/identify-exported-sonames-in-a-path as it reports the NEEDED entries present in the files within a given path. You can then compare it with the libraries that are exported to make sure that, when cross-building a firmware image, you're not bringing in dependencies from the build host.

The short version of it as can be seen in the same output is

scanelf -RBnq -F "+n#f" $1 | tr ',' '\n' | sort -u