Strip directory from filename in checksum output

Assuming your filenames don't contain spaces, here are are sed and awk solution:

A simpler sed:

cksum path/to/f.txt | sed 's/ .*[/ ]/ /'

878395353 f.txt

This sed starts match from space character and matches until it gets last / or space since .* is greedy. We just replace this matched text with a single space.

Or a simpler awk using / or space as input field separator:

cksum path/to/f.txt | awk -F '[ /]' '{print $1, $NF}'

878395353 f.txt

Based on man cksum

The cksum utility writes to the standard output three whitespace separated fields for each input file. These fields are a checksum CRC, the total number of octets in the file and the file name.

Using sed you could use 3 capture groups and use group 1 and 3 in the replacement.

([^[:space:]]+) [^[:space:]]+ (.*/)?([^[:space:]]+)

Explanation

• ([^[:space:]]+) Group 1, match 1+ non whitespace chars
• [^[:space:]]+ Match 1+ chars other than a whitespace char between spaces
• (.*/)? Optionally match group 2 matching until the last occurrence of /
• ([^[:space:]]+) Group 3, match 1+ non whitespace chars

For example:

cksum ./file.txt # --> 3777026118 8 ./file.txt

Using sed

cksum ./file.txt | sed -E 's~([^[:space:]]+) [^[:space:]]+ (.*/)?([^[:space:]]+)~\1 \3~' 

Output

3777026118 file.txt

Using awk printing the first field and the last item from the result of splitting the 3rd field:

cksum ./file.txt | awk '
{
  n=split($3,a,"/")
  print $1, a[n]
}'

Output

3777026118 file.txt

Awk can do this. For example:

awk '{ printf("%d", $1); n=split($2,a,"/"); print(" ", a[n])}'

Tested with:

echo "1237668 path/path2/f1.txt"  | awk  '{ printf("%d", $1); n=split($2,a,"/"); print(" ", a[n])}'

1237668  f1.txt

The first element is just a print with $1 in the printf. The second is a split on / then print the last element:

How to split a delimited string into an array in awk?

how to access last index of array from split function inside awk?

Note: I do not know the Cksum command you use. My cksum outputs 3 fields: checksum, size and filename. Adapt the indexes in the following if yours behaves differently.

If your shell is bash, you could use a bash array and basename. If you don't have spaces in your filenames:

$ a=($(cksum path/path2/f1.txt))
$ printf '%s %s\n' "${a[0]}" "$(basename ${a[2]})"
857691210 f1.txt

If you have spaces in your filenames, adapt the printf parameters:

$ a=($(cksum "path/path2/f 1.txt"))
$ printf '%s %s\n' "${a[0]}" "$(basename "${a[*]:2}")"
857691210 f 1.txt

And if you prefer quoting the filename:

$ printf '%s "%s"\n' "${a[0]}" "$(basename "${a[*]:2}")"
857691210 "f 1.txt"

You can also use:

cd $(dirname path/path2/f1.txt); cksum $(basename path/path2/f1.txt)

or, to keep the current directory the same:

a=$(pwd); cd $(dirname path/path2/f1.txt); cksum $(basename path/path2/f1.txt); cd $a

Assuming the / character only occurs in field #2, delete everything after field #2; then remove the directory name:

 Cksum path/path2/f1.txt | 
 sed 's# [^/]*$##;s# .*/# #'