Bash脚本开发求助：如何修改脚本以正确显示用户所属组的用户名信息

Hey there! Let's work through fixing this script together—you're already on the right track, just a few key tweaks are needed to get it working as expected.

First, Let's Break Down the Issues in Your Original Script #

Your current code has a couple of critical problems that are blocking it from showing the username correctly:

• The GroupsOfUser function doesn't accept or use the parameter you passed (/etc/group/passwd—that path is also incorrect, since /etc/passwd and /etc/group are separate system files for user and group data).
• Running groups without a username argument returns your current user's groups, not the target user's you want to check.
• The echo statement has an empty $() placeholder, so no username value gets inserted, and the output order is reversed from what you need.

Here's the Corrected Script #

GroupsOfUser() {
    # Check if a username was provided when calling the function
    if [ -z "$1" ]; then
        echo "Oops! Please provide a username. Usage: GroupsOfUser <username>"
        return 1
    fi

    # Store the target username in a variable for easy reuse
    local target_user="$1"

    # Fetch and clean up the list of groups the user belongs to
    # The `groups` command outputs like: "user : group1 group2 group3"
    # We extract everything after the colon, then trim extra spaces
    local user_groups=$(groups "$target_user" | cut -d ':' -f 2 | xargs)

    # Loop through each group and print the required format
    for group in $user_groups; do
        echo "$target_user is part of the group $group"
    done
}

# Example: Call the function with a username (replace "mohamed" with your target user)
GroupsOfUser "mohamed"

How This Works (Step by Step) #

1. Parameter Check: The script first verifies you provided a username. If not, it shows a friendly usage prompt to avoid confusion.
2. Store Username: We save the input username to a variable (target_user) so we can easily reference it throughout the script.
3. Fetch & Clean Groups: The groups "$target_user" command pulls all groups the user belongs to. We use cut to remove the username prefix (everything before the colon) and xargs to clean up extra spaces, leaving a neat space-separated list of groups.
4. Loop & Output: We iterate over each group in the list and print the exact format you requested: <username> is part of the group <group>.

Testing the Script #

To test it, just replace "mohamed" in the final line with any valid username on your system (like root or your own username). You'll see output like:

mohamed is part of the group mohamed
mohamed is part of the group adm
mohamed is part of the group sudo

内容的提问来源于stack exchange，提问作者Mohamed ali Lemkecher