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Commands tagged IFS from sorted by
Terminal - Commands tagged IFS - 5 results
each() { (IFS=$'\n'; echo "$*") }
2010-10-02 06:51:44
User: BobbyTables
Functions: echo
Tags: xargs IFS
1

This can be useful for transforming command-line args into input for xargs (one per line). This can also be done with ls if the args are filenames, but that's getting awfully close to Useless Use of Cat territory (http://partmaps.org/era/unix/award.html).

joinargs() { (IFS="$1"; shift && echo "$*") }
while [[ COUNTER -le 10 && IFS=':' ]]; do for LINE in $(cat /tmp/list); do some_command(s) $LINE; done; COUNTER=$((COUNTER+1)); done
2010-09-01 15:09:59
User: slashdot
Functions: cat
0

At times I find that I need to loop through a file where each value that I need to do something with is not on a separate line, but rather separated with a ":" or a ";". In this instance, I create a loop within which I define 'IFS' to be something other than a whitespace character. In this example, I iterate through a file which only has one line, and several fields separated with ":". The counter helps me define how many times I want to repeat the loop.

ifs () { echo -n "${IFS}"|hexdump -e '"" 10/1 "'\''%_c'\''\t" "\n"' -e '"" 10/1 "0x%02x\t" "\n\n"'|sed "s/''\|\t0x[^0-9]//g; $,/^$/d"
2009-10-10 22:41:35
User: dennisw
Functions: echo hexdump sed
2

You can display, save and restore the value of $IFS using conventional Bash commands, but these functions, which you can add to your ~/.bashrc file make it really easy.

To display $IFS use the function ifs shown above. In the sample output, you can see that it displays the characters and their hexadecimal equivalent.

This function saves it in a variable called $saveIFS:

sifs () { saveIFS=$IFS; }

Use this function to restore it

rifs () { IFS=$saveIFS; }

Add this line in your ~/.bashrc file to save a readonly copy of $IFS:

declare -r roIFS=$IFS

Use this function to restore that one to $IFS

rrifs () { IFS=$roIFS; }
export IFS=$(echo -e "\n")
2009-07-09 15:25:37
User: darkpand
Functions: echo export
8

When you use a "for" construct, it cycles on every word. If you want to cycle on a line-by-line basis (and, well, you can't use xargs -n1 :D), you can set the IFS variable to .