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How to loop over the lines of a file?
There, empty lines are preserved, but note that it would skip the last line if it was not properly delimited by a newline character. For what it is worth, I need to do that quite often, and can never remember the exact way of using while IFS= read…, so I defined the following function in my bash profile:
How to loop through lines of text in a shell script?
1. Using the sed command to remove/delete empty lines or leading and trailing whitespace in a text file The text files that my shell script process could include empty lines or leading and trailing whitespace that probably makes the files readable to the author.
How to do a bash for loop in one line?
The generic syntax for a Bash for loop in one line is the following: for i in [LIST]; do [COMMAND]; done. Let’s print the content of our text file with a one line for loop: #!/bin/bash FILENAME=”european-cities.txt” LINES=$ (cat $FILENAME) for LINE in $LINES; do echo $LINE; done.
How to read the last line of a file?
For more in-depth discussion see this StackOverflow discussion: How to use “while read” (Bash) to read the last line in a file if there’s no newline at the end of the file? Beware: this approach adds an additional newline to the last line if there is none already.
How to iterate over lines from multiple input files?
Close the current file so that the next iteration will read the first line from the next file (if any); lines not read from the file will not count towards the cumulative line count. The filename is not changed until after the first line of the next file has been read.
How does the for loop work in myfile?
As the for loop iterates through each line of the file the loop variable will contain the current line of the file as a string of characters. The general pattern for processing each line of a text file is as follows: for line in myFile: statement1 statement2