SHELL

shell count lines output

$ somecommand | wc -l

shell count number of lines

$ wc -l < /dir/file.txt
3272485

bash count lines

wc -l

count new lines bash

command | wc -l  
wc -l < some_file.txt

count lines in bash script

# Let's use a text file called file.txt
# the file contains 5 lines of some programming languages in use today:

$ cat file.txt
#Output:
#	JavaScript
#	Java
#	C
#	Python
#	C#


# Method 1 'wc'
# 'wc' command can be used to find the number of lines, characters,
# words, and bytes of a file.

$ wc -l file.txt

# Or

$ wc -l < file.txt

# Or

$ wc -l file.txt

# Output:
#	10 file.txt

# OR

# Method 2 - 'sed'
# 'sed' is a stream editor that can be used to perform basic text transformation 
# of an input file.
# This command is mostly used for find-and-replace functionality and 
# can also be used to find the number of lines of a specified file.

$ sed -n '=' file.txt
# Output:
#	1
#	2
#	3
#	4
#	5

# Or 

# sed -n '$='  which gives the overall number of lines
$ sed -n '$=' file.txt
# Output:
#	5