I’m studying bash, and I came across this Stackoverflow thread which contains this bit of code:
var="abcde"
echo ${var%d*}
The output is abc, but I can’t figure out why. I understand that %d is used to indicate an integer number and * represents anything, but I can’t figure out why those together would truncate var to only 3 characters.
Would like to add, don’t do this or shoulda used Python.
Manipulating strings in bash is a mistake and creates spaghetti code. This goes for sed and awk as well.
Python equivalent
str_x = "abcde" pos = str_x.index("d") ret = str_x[:pos] print(ret)In one line, capturing the output into a bash variable
ret=$(python -c 'str_x = "abcde"; pos = str_x.index("d"); ret = str_x[:pos]; print(ret)')You may be confusing that %d with printf syntax. I’m not entirely sure, but I think what the percent sign means is delete everything from the end of string until the first occurence of letter “d”
