IMHO putting some sort of third party parsing logic into your script is usually better than cobbling together yourself. If necessary I could prefix each line with the name of the array .... e.g. The line is split into fields as with word splitting, and the first word is assigned to the first NAME, the second You can load the content of the file line by line into an array. Also, code in C will not help or speed up (or not worth your time) if awk can not perform well. The Overflow Blog Open source has a funding problem. You might be able to find something that seems to work for the data you've seen so far but it's generally safer to use logic someone else has vetted. You can print the total number of the files array elements, i.e. awk is a real winner when it comes to processing large file size. Iâm just getting started with scripting and I am needing some help reading a file into the script. In a script, these commands are executed in series automatically, much like a C or Python program. Shell Scripting with Bash. I have tested and worked on real UNIX (HP-UX v11.0) not on GNU/Linux (no offense, Linux is wonderful too but OIL industry likes to spends its money on HP stuff) tools so YMMV. for line in "${my_array[@]}"; do # process the lines done More about the shell builtins read and readarray commands - GNU. More about IFS - Wikipedia. In the above example, each index of an array element has printed through for loop. Reads a single line from the standard input, or from file descriptor FD if the -u option is supplied. Mapfile is a convenient way to read lines from a file into an indexed array, not as portable as read but slightly faster. To Read File line by line in Bash Scripting, following are some of the ways explained in detail. Bash 101 Hacks, by Ramesh Natarajan. This page explained how to read file line by line in bash shell script. It is also possible to store the elements in a bash array using the -a option. ... Browse other questions tagged command-line bash scripts or ask your own question. mapfile -t my_array < my_file And then. You can also update the value of any element of an array; for example, you can change the value of the first element of the files array to âa.txtâ using the following assignment: files[0]="a.txt" Adding array elements in bash. Example â Using While Loop. Following is the syntax of reading file line by line in Bash using bash while loop : Syntax Hi - I have a file that contains data in this format:-#comment value1 value2 value3 #comment value4 value5 value6 value7 #comment value8 value9 I need to read value1, value2 and value3 into one array, value4 value5 value6 and value7 into another array and value8 and value9 into a 3rd array. augeas has a property file lens so using augtool to retrieve whatever values you're interested in was another possible. the size of the array: echo ${#files[@]} 5. By using for loop you avoid creating a subshell. A shell script is a file containing one or more commands that you would type on the command line. I spend most of my time on Linux environment. ... $ ./loadcontent.sh Welcome to thegeekstuff Linux Unix Read file content! Recommended Reading. ... Hi guys. It gives a b which is way simpler and more straight-forward than any workaround given by the answers of Read values into a shell variable from a pipe and in bash read after a pipe is not setting values. Bash Read File line by line. Here are some examples of common commands: cat: Display content in a file or combine two files together. read: read [-ers] [-a array] [-d delim] [-i text] [-n nchars] [-N nchars] [-p prompt] [-t timeout] [-u fd] [name ...Read a line from the standard input and split it into fields. Reading a whole file into an array (Bash versions 4x and later) readarray -t my_array < my_file or. Needing some help reading a file into an indexed array, not portable... Is split into fields as with word splitting, and the first word is to. Store the elements in a script, these commands are executed in series automatically, much like C... The array: echo $ { # files [ @ ] } 5 an array element has printed for. 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