xargs -I % command -option1 % -option2 % under cygwin

Question

I learned from answers under this question: Making xargs work in Cygwin that option xargs -I does not work properly under Cygwin. There were some workarounds, but unfortunately it does not help in my case.

My question is, how can I approach the same result as:

..somthing that produces multiple lines.. | xargs -I % command -option1 % -option2 %

under Cygwin environment?

Edit:

To clarify, I would like to get some values from stdin and invoke the "command", putting them into two places as its arguments "%". I would like to invoke my command multiple times on a data produced by the "something".

Example 1: (i haven't been programming in cpp for a huge time so please forgive me mistakes)

find -name *.cpp | cut -d. -f1 | xargs -I % gcc -o %.o -I %.h %.cpp

Example 2:

cat songs_to_process.txt | xargs -I % convert --format=mp3 --source=%.avi --output=%.mp3

Your question is unclear. What should happen to each line of the output? — choroba, Dec 17 '17 at 19:52
@choroba I have edited my question, thank you for making a notice. — mpasko256, Dec 17 '17 at 20:15
What version of cygwin do you have? What error are you getting? — choroba, Dec 17 '17 at 20:18
uname -r returns 2.6.0(0.304/5/3), maybe shall I update to 2.9... — mpasko256, Dec 17 '17 at 20:24
Is your `xargs` actually from Cygwin? Does `xargs --version` give you anything useful? Does `type xargs` show it's coming from the same directory where, say, `type find` says the `find` binary is at? — Charles Duffy, Dec 17 '17 at 20:37
`xargs -I` is [mandatory for a POSIX-compliant implementation](http://pubs.opengroup.org/onlinepubs/9699919799/utilities/xargs.html), so it's not like a different/old Cygwin `xargs` wouldn't have it. — Charles Duffy, Dec 17 '17 at 20:38
@CharlesDuffy `xargs --version` reads: "Packaged by Cygwin (4.6.0-1)" `type xargs` and `which xargs` gives: (/usr/bin/xargs) — mpasko256, Dec 17 '17 at 20:43
That's... astonishing, frankly. I'll want to reproduce at some point when I have a windows machine on hand. — Charles Duffy, Dec 17 '17 at 20:50

Charles Duffy · Accepted Answer · 2017-12-17T20:41:08.900

You don't need xargs for this job at all -- not in any of your examples.

find . -name '*.cpp' -print0 | while IFS= read -r -d '' filename; do
  basename=${filename%.*}
  gcc -o "${basename}.o" -I "${basename}.h" "${basename}.cpp"
done

...or:

while IFS= read -r song; do
    song=${song%$'\r'} # repair if your input file is in DOS (CRLF) format
    convert --format=mp3 --source="$song".avi --output="$song".mp3
done <songs_to_process.txt

See BashFAQ #1 for an introduction to best practices for processing inputs line-by-line in bash.

xargs -I % command -option1 % -option2 % under cygwin

1 Answers1