On a test server I purposefully deleted `?????` in `/` - I was expecting the symlink `/lib64` and the `/media` directory to be deleted. All went well (everything broke), but then I was curious about the output below:

```
[root@testserver /]# ls
bin  boot  dev  etc  home  lib  lib64  media  mnt  opt  proc  rh_share3  root  run  sbin  srv  sys  tmp  usr  var
[root@testserver /]# rm -rf ?????
bash: /usr/bin/sed: No such file or directory
[root@testserver /]# ls
bash: /usr/bin/ls: No such file or directory
bash: /usr/bin/sed: No such file or directory

```

I see that some packages have `sed` as a dependency, but I'm not understanding why it's calling `sed` for something as simple as pressing `Enter`

```
[root@testserver bin]# rpm -q --whatrequires sed
krb5-libs-1.17-18.el8.x86_64
ca-certificates-2019.2.32-80.0.el8_1.noarch
dracut-049-70.git20200228.el8.x86_64
crypto-policies-20191128-2.git23e1bf1.el8.noarch
policycoreutils-2.9-9.el8.x86_64
authselect-libs-1.1-2.el8.x86_64
cups-filters-1.20.0-19.el8.x86_64
open-vm-tools-11.0.0-4.el8.x86_64
authselect-compat-1.1-2.el8.x86_64
dhcp-client-4.3.6-40.el8.x86_64
nfs-utils-2.3.3-31.el8.x86_64
autofs-5.1.4-40.el8.x86_64

```

Why does the line `bash: /usr/bin/sed: No such file or directory` show up? Obviously `sed` is considered missing, but why is it being called at all? It is also not mentioned if I just run a `strace -o bash bash`. I know `sed` stands for `stream editor` - is every bash command run through `sed`, or what else could be going on?

The OS is an OOTB RHEL 8.2 (Oopta) with a GUI.

**EDIT**

Below is the output of `set | grep sed`:

```
[user1@testserver ~]$ set | grep sed
    local command=$(HISTTIMEFORMAT= history 1 | sed 's/^ *[0-9]\+ *//');
                COMPREPLY=($( compgen -W "$( bpftool help 2>&1 |                     command sed                     -e '/OBJECT := /!d'                     -e 's/.*{//'                     -e 's/}.*//'                     -e 's/|//g' )" -- "$cur" ));
    COMPREPLY+=($( compgen -W "$( bpftool -jp btf 2>&1 |         command sed -n 's/.*"id": \(.*\),$/\1/p' )" -- "$cur" ))
    COMPREPLY+=($( compgen -W "$( bpftool -jp map  2>&1 |         command sed -n 's/.*"id": \(.*\),$/\1/p' )" -- "$cur" ))
    COMPREPLY+=($( compgen -W "$( bpftool -jp map  2>&1 |         command grep -C2 "$type" |         command sed -n 's/.*"id": \(.*\),$/\1/p' )" -- "$cur" ))
    COMPREPLY+=($( compgen -W "$( bpftool -jp prog 2>&1 |         command sed -n 's/.*"id": \(.*\),$/\1/p' )" -- "$cur" ))
    COMPREPLY+=($( compgen -W "$( bpftool -jp prog 2>&1 |         command sed -n 's/.*"tag": "\(.*\)",$/\1/p' )" -- "$cur" ))
    type=$(bpftool -jp map show $keyword $ref |         command sed -n 's/.*"type": "\(.*\)",$/\1/p');
        COMPREPLY=($( compgen -W "$( command sed -ne 's|^iface \([^ ]\{1,\}\).*$|\1|p'            /etc/network/interfaces /etc/network/interfaces.d/* 2>/dev/null )"             -- "$cur" ));
            COMPREPLY=($( compgen -W "$( printf '%s\n'             /etc/sysconfig/network/ifcfg-* |             command sed -ne 's|.*ifcfg-\([^*].*\)$|\1|p' )" -- "$cur" ));
                COMPREPLY=($( compgen -W "$( command ls -B             /etc/sysconfig/interfaces |             command sed -ne 's|.*ifcfg-\([^*].*\)$|\1|p' )" -- "$cur" ));
                COMPREPLY=($( compgen -W "$( printf '%s\n'             /etc/sysconfig/network-scripts/ifcfg-* |             command sed -ne 's|.*ifcfg-\([^*].*\)$|\1|p' )" -- "$cur" ));
    local included=$( command sed -ne 's/^[[:blank:]]*[Ii][Nn][Cc][Ll][Uu][Dd][Ee][[:blank:]]\{1,\}\([^#%]*\)\(#.*\)\{0,1\}$/\1/p' "${configfile}" );
    COMPREPLY+=($( compgen -W         "$( { LC_ALL=C ifconfig -a || ip addr show; } 2>/dev/null | command sed -ne             's/.*addr:\([^[:space:]]*\).*/\1/p' -ne             's|.*inet[[:space:]]\{1,\}\([^[:space:]/]*\).*|\1|p' )"         -- "$cur" ))
    [[ $# -ge $OPTIND ]] && echo "error: $FUNCNAME("$@"): unprocessed arguments:" $(while [[ $# -ge $OPTIND ]]; do printf '%s\n' ${!OPTIND}; shift; done);
        local hosts=$( command sed -ne 's/^[[:blank:]]*[Hh][Oo][Ss][Tt][[:blank:]]\{1,\}\([^#*?%]*\)\(#.*\)\{0,1\}$/\1/p' "${config[@]}" );
            local argtype=$( LC_ALL=C $1 --help 2>&1 | command sed -ne                 "s|.*$prev\[\{0,1\}=[<[]\{0,1\}\([-A-Za-z0-9_]\{1,\}\).*|\1|p" );
        COMPREPLY=($( compgen -W "$( LC_ALL=C $1 --help 2>&1 |             command sed -ne 's/.*\(--[-A-Za-z0-9]\{1,\}=\{0,1\}\).*/\1/p' | sort -u )"             -- "$cur" ));
    COMPREPLY+=($(         { LC_ALL=C ifconfig -a || ip link show; } 2>/dev/null | command sed -ne         "s/.*[[:space:]]HWaddr[[:space:]]\{1,\}\($re\)[[:space:]].*/\1/p" -ne         "s/.*[[:space:]]HWaddr[[:space:]]\{1,\}\($re\)[[:space:]]*$/\1/p" -ne         "s|.*[[:space:]]\(link/\)\{0,1\}ether[[:space:]]\{1,\}\($re\)[[:space:]].*|\2|p" -ne         "s|.*[[:space:]]\(link/\)\{0,1\}ether[[:space:]]\{1,\}\($re\)[[:space:]]*$|\2|p"
    COMPREPLY+=($( { arp -an || ip neigh show; } 2>/dev/null | command sed -ne         "s/.*[[:space:]]\($re\)[[:space:]].*/\1/p" -ne         "s/.*[[:space:]]\($re\)[[:space:]]*$/\1/p" ));
    COMPREPLY+=($( command sed -ne         "s/^[[:space:]]*\($re\)[[:space:]].*/\1/p" /etc/ethers 2>/dev/null ));
    COMPREPLY=($( compgen -W "$( command ls -RL $modpath 2>/dev/null |         command sed -ne 's/^\(.*\)\.k\{0,1\}o\(\.[gx]z\)\{0,1\}$/\1/p' )" -- "$cur" ))
        COMPREPLY=($( compgen -X '<defunct>'             -W '$( command ps axo comm | command sed -e 1d )' -- "$cur" ));
        COMPREPLY=($( compgen -X '<defunct>' -W '$( command ps axo command= | command sed -e \
        COMPREPLY=($( compgen -W '`command sed -e "y/|/ /" \
    COMPREPLY+=($( compgen -W         "$( command sed -ne 's/^\([^[:space:]#|]\{2,\}\)|.*/\1/p' /etc/termcap             2>/dev/null )" -- "$cur" ));

```