Miller features in the context of the Unix toolkit

File-format awareness

Miller respects CSV headers. If you do mlr --csv-input cat *.csv then the header line is written once:

$ cat a.csv
a,b,c
1,2,3
4,5,6

$ cat b.csv
a,b,c
7,8,9

$ mlr --csv cat a.csv b.csv
a,b,c
1,2,3
4,5,6
7,8,9

$ mlr --csv sort -nr b a.csv b.csv
a,b,c
7,8,9
4,5,6
1,2,3

Likewise with mlr sort, mlr tac, and so on.

awk-like features: mlr filter and mlr put

See also

See Reference for more on Miller’s subcommands cat, cut, head, sort, tac, tail, top, and uniq, as well as awk-like mlr filter and mlr put.