diff --git a/share/completions/adduser.fish b/share/completions/adduser.fish
index 33d28182a..e55ff1c7d 100644
--- a/share/completions/adduser.fish
+++ b/share/completions/adduser.fish
@@ -16,7 +16,7 @@ complete -c adduser -l group --description 'When combined with --system, a group
 complete -c adduser -l help --description 'Display brief instructions'
 complete -c adduser -l home --description 'Use specified directory as the user\'s home directory' -x -a '(__fish_complete_directories)'
 complete -c adduser -l shell --description 'Use shell as the user\'s login shell, rather than the default specified by the configuration file' -x -a '(cat /etc/shells)'
-complete -c adduser -l ingroup --description 'Add the new user to GROUP instead of a usergroup or the default group defined by USERS_GID in the configuration file' -x -a '(cat /etc/group|cut -d : -f 1)'
+complete -c adduser -l ingroup --description 'Add the new user to GROUP instead of a usergroup or the default group defined by USERS_GID in the configuration file' -x -a '(cut -d : -f 1 /etc/group)'
 complete -c adduser -l no-create-home --description 'Do not create the home directory, even if it doesni\'t exist'
 complete -c adduser -l quiet --description 'Suppress informational messages, only show warnings and errors'
 complete -c adduser -l debug --description 'Be verbose, most useful if you want to nail down a problem with adduser'
diff --git a/share/completions/setxkbmap.fish b/share/completions/setxkbmap.fish
index 71aab63e8..6a557fb70 100644
--- a/share/completions/setxkbmap.fish
+++ b/share/completions/setxkbmap.fish
@@ -2,23 +2,23 @@
 set -l filter '"s/\S+\s\S+\s(.+)\((.+)\)/\1\t\2/;"'
 
 complete -c setxkbmap -o '?' -o help -d 'Print this message'
-complete -c setxkbmap -o compat    -d 'Specifies compatibility map component name' -xa "(cat /usr/share/X11/xkb/compat.dir | sed -r $filter)"
+complete -c setxkbmap -o compat    -d 'Specifies compatibility map component name' -xa "(sed -r $filter /usr/share/X11/xkb/compat.dir)"
 complete -c setxkbmap -o config    -d 'Specifies configuration file to use' -r
 complete -c setxkbmap -o device    -d 'Specifies the device ID to use' -x
 complete -c setxkbmap -o display   -d 'Specifies display to use' -x
-complete -c setxkbmap -o geometry  -d 'Specifies geometry component name' -xa "(cat /usr/share/X11/xkb/geometry.dir | sed -r $filter)"
+complete -c setxkbmap -o geometry  -d 'Specifies geometry component name' -xa "(sed -r $filter /usr/share/X11/xkb/geometry.dir)"
 complete -c setxkbmap -o I         -d 'Add <dir> to list of directories to be used' -xa '(__fish_complete_directories)'
-complete -c setxkbmap -o keycodes  -d 'Specifies keycodes component name' -xa "(cat /usr/share/X11/xkb/keycodes.dir | sed -r $filter)"
-complete -c setxkbmap -o keymap    -d 'Specifies name of keymap to load' -xa "(cat /usr/share/X11/xkb/keymap.dir | sed -r $filter)"
+complete -c setxkbmap -o keycodes  -d 'Specifies keycodes component name' -xa "(sed -r $filter /usr/share/X11/xkb/keycodes.dir)"
+complete -c setxkbmap -o keymap    -d 'Specifies name of keymap to load' -xa "(sed -r $filter /usr/share/X11/xkb/keymap.dir)"
 complete -c setxkbmap -o layout    -d 'Specifies layout used to choose component names' -xa "(__fish_complete_setxkbmap layout)"
 complete -c setxkbmap -o model     -d 'Specifies model used to choose component names' -xa "(__fish_complete_setxkbmap model)"
 complete -c setxkbmap -o option    -d 'Adds an option used to choose component names' -xa "(__fish_complete_list , '__fish_complete_setxkbmap option')"
 complete -c setxkbmap -o print     -d 'Print a complete xkb_keymap description and exit'
 complete -c setxkbmap -o query     -d 'Print the current layout settings and exit'
 complete -c setxkbmap -o rules     -d 'Name of rules file to use' -x
-complete -c setxkbmap -o symbols   -d 'Specifies symbols component name' -xa "(cat /usr/share/X11/xkb/symbols.dir | sed -r $filter)"
+complete -c setxkbmap -o symbols   -d 'Specifies symbols component name' -xa "(sed -r $filter /usr/share/X11/xkb/symbols.dir)"
 complete -c setxkbmap -o synch     -d 'Synchronize request w/X server'
-complete -c setxkbmap -o types     -d 'Specifies types component name' -xa "(cat /usr/share/X11/xkb/types.dir | sed -r $filter)"
+complete -c setxkbmap -o types     -d 'Specifies types component name' -xa "(sed -r $filter /usr/share/X11/xkb/types.dir)"
 complete -c setxkbmap -o v -o verbose -d 'Sets verbosity (1..10).  Higher values yield more messages' -xa '(seq 1 10)'
 complete -c setxkbmap -o variant   -d 'Specifies layout variant used to choose component names' -xa "(__fish_complete_setxkbmap variant)"
 
diff --git a/share/completions/ssh.fish b/share/completions/ssh.fish
index a8896b627..2d9c40b74 100644
--- a/share/completions/ssh.fish
+++ b/share/completions/ssh.fish
@@ -23,7 +23,7 @@ complete -c ssh -s a --description "Disables forwarding of the authentication ag
 complete -c ssh -s A --description "Enables forwarding of the authentication agent"
 complete -x -c ssh -s b --description "Interface to transmit from" -a "
 (
-	cat /proc/net/arp ^/dev/null| string match -r -v '^IP'|cut -d ' ' -f 1 ^/dev/null
+	tail -n +2 /proc/net/arp | cut -d ' ' -f 1 ^/dev/null
 )
 "
 
diff --git a/share/completions/umount.fish b/share/completions/umount.fish
index 85929fb82..7b164a071 100644
--- a/share/completions/umount.fish
+++ b/share/completions/umount.fish
@@ -16,7 +16,7 @@ complete -c umount -s d --description "In case the unmounted device was a loop d
 complete -c umount -s i --description "Don't call the /sbin/umount.<filesystem> helper even if it exists"
 complete -c umount -s a --description "Unmount all of the file systems described in /etc/mtab"
 complete -c umount -s t --description "Actions should only be taken on file systems of the specified type" -xa "(__fish_print_filesystems)"
-complete -c umount -s O --description "Actions should only be taken on file systems with the specified options in /etc/fstab" -xa '(cat /etc/mtab | cut -d " " -f 4)\t"Mount option"'
+complete -c umount -s O --description "Actions should only be taken on file systems with the specified options in /etc/fstab" -xa '(cut -d " " -f 4 /etc/mtab)\t"Mount option"'
 complete -c umount -s f --description "Force unmount (in case of an unreachable NFS system)"
 complete -c umount -s l --description "Detach the filesystem from the filesystem hierarchy now, and cleanup all references to the filesystem as soon as it is not busy"
 
diff --git a/share/completions/useradd.fish b/share/completions/useradd.fish
index 37c9a7290..0719d6196 100644
--- a/share/completions/useradd.fish
+++ b/share/completions/useradd.fish
@@ -7,7 +7,7 @@
 
 complete -c useradd -s c -l comment --description 'A comment about this user' -r
 complete -c useradd -s d -l home --description 'Home directory for the new user' -x -a '(__fish_complete_directories)'
-complete -c useradd -s G -l groups --description 'Supplementary groups' -xa '(__fish_append , (cat /etc/group|cut -d : -f 1))'
+complete -c useradd -s G -l groups --description 'Supplementary groups' -xa '(__fish_append , (cut -d : -f 1 /etc/group))'
 complete -c useradd -s h -l help --description 'Display help message and exit'
 complete -c useradd -s m -l create-home --description 'The user\'s home directory will be created if it does not exist'
 complete -c useradd -s n --description 'A group having the same name as the user being added to the system will be created by default (when -g is not specified)'
diff --git a/share/functions/__fish_print_function_prototypes.fish b/share/functions/__fish_print_function_prototypes.fish
index 862b8dcc9..a29ab5b10 100644
--- a/share/functions/__fish_print_function_prototypes.fish
+++ b/share/functions/__fish_print_function_prototypes.fish
@@ -1,5 +1,5 @@
 
 function __fish_print_function_prototypes -d "Prints the names of all function prototypes found in the headers in the current directory"
-    cat *.h* | sed -n "s/^\(.*[^[a-zA-Z_0-9]\|\)\([a-zA-Z_][a-zA-Z_0-9]*\) *(.*);.*\$/\2/p"
+    sed -n "s/^\(.*[^[a-zA-Z_0-9]\|\)\([a-zA-Z_][a-zA-Z_0-9]*\) *(.*);.*\$/\2/p" *.h*
 end
 
diff --git a/share/functions/__fish_print_packages.fish b/share/functions/__fish_print_packages.fish
index 1dc0893c4..c3985cd13 100644
--- a/share/functions/__fish_print_packages.fish
+++ b/share/functions/__fish_print_packages.fish
@@ -56,7 +56,7 @@ function __fish_print_packages
     if type -q -f zypper
         # Use libzypp cache file if available
         if test -f /var/cache/zypp/solv/@System/solv.idx
-            cat /var/cache/zypp/solv/*/solv.idx | awk '!/application:|srcpackage:|product:|pattern:|patch:/ {print $1'\t$package'}'
+            awk '!/application:|srcpackage:|product:|pattern:|patch:/ {print $1'\t$package'}' /var/cache/zypp/solv/*/solv.idx
             return
         end
 
diff --git a/share/functions/__fish_print_xdg_mimetypes.fish b/share/functions/__fish_print_xdg_mimetypes.fish
index 39f9a2798..dd1e28c13 100644
--- a/share/functions/__fish_print_xdg_mimetypes.fish
+++ b/share/functions/__fish_print_xdg_mimetypes.fish
@@ -1,5 +1,3 @@
 function __fish_print_xdg_mimetypes --description 'Print XDG mime types'
-    cat ~/.local/share/applications/mimeinfo.cache | grep -v "\[MIME Cache\]" | tr = \t
-    cat /usr/share/applications/mimeinfo.cache | grep -v "\[MIME Cache\]" | tr = \t
-
+    sed -e '/\[MIME Cache\]/d; y!=!\t!' ~/.local/share/applications/mimeinfo.cache /usr/share/applications/mimeinfo.cache
 end