5 ms·

Ask HN: What are your favorite UNIX tools?

11 points by aadhavans 2y ago

Either built-in tools, or those that follow the UNIX philosophy. My favorite hidden gems in a base UNIX install are `tac` (print lines in reverse order) and `tr` (character substitutions).

dcdevito 2y ago
[dead]
PaulHoule 2y ago
awk (It's a guilty pleasure to write shell pipelines that use awk to write a shell script and then pipe that script in sh, I find it easier than looking up the bizzaro syntax for loops in bash in the info pages.)
- aadhavans 2y ago
  > use awk to write a shell script Do you have any examples of this?
  - PaulHoule 2y ago
    How about ls -l *.txt | awk '{if ($5<2000) print "cat " $9}' | sh to cat text files that are less than 2000 bytes long
bediger4000 2y ago
tr is surprisingly useful. If you're clever, the -c and -d flags can do good things. wc is also useful, mostly as "wc -l". If you keep data in line oriented, human readable form, "wc -l" counts data items.
manbart 2y ago
xclock with the cat theme
deleted 2y ago
[deleted]
t-3 2y ago
perl-rename - rename is also good, but much more annoying to use for me as it doesn't use standard regex notation like perl-rename. printf - shell is natively great at interpolation already, but having C-style printf formatting is often useful and echo has a lot of footguns
caprock 2y ago
ctrl-r in bash tops my list, even if it's not quite what you are thinking of as a unix tool. Probably the pipe itself would be my favorite next. Then in no particular order: tail, cut, xargs, wc, tr, grep, sort, uniq.
kasperset 2y ago
find My command to backup selected file using Tarsnap. find /Users/xyz/Analysis -type f $ -name '.pdf' -o -name '.docx' $ -print0 | tarsnap --dry-run --no-default-config --print-stats --humanize-numbers -c --null -T- This command file files ending with docx and pdf to back with tarsnap. The "-" following the "-T" option allows to pass the name using std-in via find command
vermasque 2y ago
pbpaste and pbcopy to read and write to the clipboard and then combine with your favorite grep, sed, tr, cut, etc.
wruza 2y ago
Most: grep, find, cat, sort, tail, wc, ls, sudo, pgrep. Interesting: comm: https://linux.die.net/man/1/comm https://linux.die.net/man/1/comm Compare sorted files FILE1 and FILE2 line by line. With no options, produce three-column output. Column one contains lines unique to FILE1, column two contains lines unique to FILE2, and column three contains lines common to both files. -1 suppress column 1 (lines unique to FILE1) -2 suppress column 2 (lines unique to FILE2) -3 suppress column 3 (lines that appear in both files) Weak: adduser/useradd (hard to non-interactive), chmod (could use file/dir filter with -R). Least: systemctl, journalctl.
- commandersaki 2y ago
  One trick I learned from a UNIX greybeard in my junior days before pgrep was widely avaialble is: ps auxw | grep [p]rocessname and it will eschew the grep process in the list.
commandersaki 2y ago
comm & awk

11 points by aadhavans 2y ago

Either built-in tools, or those that follow the UNIX philosophy. My favorite hidden gems in a base UNIX install are `tac` (print lines in reverse order) and `tr` (character substitutions).

dcdevito 2y ago

[dead]

PaulHoule 2y ago

awk (It's a guilty pleasure to write shell pipelines that use awk to write a shell script and then pipe that script in sh, I find it easier than looking up the bizzaro syntax for loops in bash in the info pages.)

aadhavans 2y ago
> use awk to write a shell script Do you have any examples of this?
- PaulHoule 2y ago
  How about ls -l *.txt | awk '{if ($5<2000) print "cat " $9}' | sh to cat text files that are less than 2000 bytes long

bediger4000 2y ago

tr is surprisingly useful. If you're clever, the -c and -d flags can do good things. wc is also useful, mostly as "wc -l". If you keep data in line oriented, human readable form, "wc -l" counts data items.

manbart 2y ago

xclock with the cat theme

deleted 2y ago

[deleted]

t-3 2y ago

perl-rename - rename is also good, but much more annoying to use for me as it doesn't use standard regex notation like perl-rename. printf - shell is natively great at interpolation already, but having C-style printf formatting is often useful and echo has a lot of footguns

caprock 2y ago

ctrl-r in bash tops my list, even if it's not quite what you are thinking of as a unix tool. Probably the pipe itself would be my favorite next. Then in no particular order: tail, cut, xargs, wc, tr, grep, sort, uniq.

kasperset 2y ago

find My command to backup selected file using Tarsnap. find /Users/xyz/Analysis -type f $ -name '.pdf' -o -name '.docx' $ -print0 | tarsnap --dry-run --no-default-config --print-stats --humanize-numbers -c --null -T- This command file files ending with docx and pdf to back with tarsnap. The "-" following the "-T" option allows to pass the name using std-in via find command

vermasque 2y ago

pbpaste and pbcopy to read and write to the clipboard and then combine with your favorite grep, sed, tr, cut, etc.

wruza 2y ago

Most: grep, find, cat, sort, tail, wc, ls, sudo, pgrep. Interesting: comm: https://linux.die.net/man/1/comm https://linux.die.net/man/1/comm Compare sorted files FILE1 and FILE2 line by line. With no options, produce three-column output. Column one contains lines unique to FILE1, column two contains lines unique to FILE2, and column three contains lines common to both files. -1 suppress column 1 (lines unique to FILE1) -2 suppress column 2 (lines unique to FILE2) -3 suppress column 3 (lines that appear in both files) Weak: adduser/useradd (hard to non-interactive), chmod (could use file/dir filter with -R). Least: systemctl, journalctl.

commandersaki 2y ago
One trick I learned from a UNIX greybeard in my junior days before pgrep was widely avaialble is: ps auxw | grep [p]rocessname and it will eschew the grep process in the list.

commandersaki 2y ago

comm & awk