Follow-up Comment #1, bug #55190 (project findutils): 1) Regarding the terms "replace" vs. "substitute": for me as non-English-native speaker, there's no difference between 'replace' and 'substitute.
Your example can be simplified by avoiding the files AAA.txt and BBB.txt: it simply reads: $ echo line | xargs -I {} echo line2 As documented both in the man page and the Texinfo manual - and even in "xargs --help", the -I option works on the "initial arguments". Looking at the synopsis clarifies: Usage: xargs/xargs [OPTION]... COMMAND [INITIAL-ARGS]... ... -I R same as --replace=R -i, --replace[=R] replace R in INITIAL-ARGS with names read from standard input; if R is unspecified, assume {} In your example above, the initial args is the string "line2". So there xargs cannot replace '{}' because there is none. 2) findutils' info pages _has_ a separate node to explain -I,-e,--replace incl. examples: https://www.gnu.org/software/findutils/manual/html_node/find_html/Interspersing-File-Names.html#Interspersing-File-Names With the above, do you see things in the documentation which could be improved? Concrete suggestions and patches welcome. ;-) Have a nice day, Berny _______________________________________________________ Reply to this item at: <https://savannah.gnu.org/bugs/?55190> _______________________________________________ Message sent via Savannah https://savannah.gnu.org/