zcat shouldn't error out if you try to zcat an uncompressed file, it should just output the damned file !

There I said it !

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Yeah, it's a pain. Leads to bad one liners:
for i in $(ls); do zcat $i || cat $i; done
- Btw, don't parse ls. Use find |while read -r instead.
  undefined
  
  find -maxdepth 1 -name "term" -print |while read -r file do zcat "$file" 2>/dev/null || cat "$file" done
  
  Won't this cause cat to iterate through all files in the cwd once zcat encounters an issue, instead of just the specific file?
  
  You are correct. This probably produces something more similar to what you'd want the original command to do, but with better safely:
  bash
  
  find -- . -type f -regex '^\./[^/]*$' -exec sh -c -- 'for file in "${@}"; do zcat "${file}" || cat "${file}" || exit; done' sh '{}' '+'
  That assumes you want to interact with files with names like .hidden.txt.gz though. If you don't, and only intend to have a directory with regular files (as opposed to directories or symbolic links or other types of file), using this is much simpler and even safer, and avoids using files in a surprising order:
  bash
  
  for i in *; do zcat -- "$i" || cat -- "$i" || exit; done
  Of course, the real solution is to avoid using the Shell Command Language at all, and to carefully adapt any program to your particular problem as needed: https://sipb.mit.edu/doc/safe-shell/
  
  Yeah, i was tired and had $file there first, then saw that you wanted to cat all in directory. Still tired, but i think this works now.
  
  You can just do for f in * (or other shell glob), unless you need find's fancy search/filtering features.
  The shell glob isn't just simpler, but also more robust, because it works also when the filename contains a newline; find .. | while read -r will crap out on that. Also apparently you want while IFS= read -r because otherwise read might trim whitespace.
  If you want to avoid that problem with the newline and still use find, you can use find -exec or find -print0 .. | xargs -0, or find -print0 .. | while IFS= read -r -d ''. I think -print0 is not standard POSIX though.
  
  because it works also when the filename contains a newline
  Doesn't that depend on the shell?
  
  I don't think so and have never heard that, but I could be wrong.
- Thanks !
  But still we shouldn't have to resort to this !
  ~~Also, can't get the output through pipe~~
  for i in $(ls); do zcat $i || cat $i; done | grep mysearchterm
  ~~this appears to work~~
  ~~find . -type f -print0 | xargs -0 -I{} sh -c 'zcat "{}" 2>/dev/null || cat "{}"' | grep "mysearchterm"~~
  ~~Still, that was a speed bump that I guess everyone dealing with mass compressed log files has to figure out on the fly because zcat can't read uncompressed files ! argg !!!~~
  for i in $(ls); do zcat $i 2>/dev/null || cat $i; done | grep mysearchterm

32 comments