UNIX for Dummies Questions & Answers

gzip -cd * | grep error | wc -l

gzip -cd $( ls -1 *.gz  | tail -100 ) ...

gzcat

#!/usr/bin/env bash

# @(#) s1	Demonstrate limiting a long list files.

# Uncomment to run script as external user.
# export PATH="/usr/local/bin:/usr/bin:/bin"
# Infrastructure details, environment, commands for forum posts. 
set +o nounset
pe() { for i;do printf "%s" "$i";done; printf "\n"; }
pl() { pe;pe "-----" ;pe "$*"; }
LC_ALL=C ; LANG=C ; export LC_ALL LANG
pe ; pe "Environment: LC_ALL = $LC_ALL, LANG = $LANG"
pe "(Versions displayed with local utility \"version\")"
c=$( ps | grep $$ | awk '{print $NF}' )
version >/dev/null 2>&1 && s=$(_eat $0 $1) || s=""
[ "$c" = "$s" ] && p="$s" || p="$c"
version >/dev/null 2>&1 && version "=o" $p find gzip
set -o nounset

# Remove and create a few *.gz files.
# Make all files except t7 contain string "error".

rm -f t? *.gz

# Display source files.
pe
pe " generic.txt:"
cat generic.txt

pe
pe " plain.txt:"
cat plain.txt

for i in 1 2 3 4 5 6 8 9
do
  cp generic.txt t$i
  gzip t$i
done

# Create file *without* string error.
cp plain.txt t7
gzip t7

pl " Seeing the list of filenames for comfort:"
find . -name '*.gz' | sort | tail -5

pl " Feeding list of files into gzip, expecting \"4\":"
gzip -cd $( find . -name '*.gz' | sort | tail -5 ) | grep error | wc -l

exit 0

% ./s1

Environment: LC_ALL = C, LANG = C
(Versions displayed with local utility "version")
OS, ker|rel, machine: Linux, 2.6.26-2-amd64, x86_64
Distribution        : Debian GNU/Linux 5.0 
GNU bash 3.2.39
find (GNU findutils) 4.4.0
gzip 1.3.12

 generic.txt:
The file has an error.

 plain.txt:
This is a plain file.

-----
 Seeing the list of filenames for comfort:
./t5.gz
./t6.gz
./t7.gz
./t8.gz
./t9.gz

-----
 Feeding list of files into gzip, expecting "4":
4