Foreach loop in csh shell script. There is a csh script (say c.

Foreach loop in csh shell script. end. It is a modle of good technical writing and will make you a true power user of csh but if you get really good with csh, you'll reach a point where you'll find there are tasks you cannot do using the limited syntax of csh, you'll need to use other tools to achieve your goal C Shell running on Windows Services for UNIX. There are two: Korn shell (ksh) and Bourne-Again-Shell (bash). tcsh shell: break Description. I'd try putting a -f in the shebang line (#!/bin/csh -f), or invoking the csh script using csh -f <file>. instead of foreach i (do stuff for i), we have foreach i j(do stuff for i; do stuff for j) I am working under BASH and TCSH shell environments cheers (3 Replies) If you really much continue using csh get a copy of the Anderson's Guide to the Csh (or similar title). @StanStrum This solution should be much quicker (O(n) time complexity) and more readable than the cut approach. #!/bin/csh -f foreach line (`cat test. Note: in regular Bourne-shell scripting setting and exporting the IFS would occur on two separate lines (IFS='x'; export IFS;). The -f tells the shell not to source your startup files, . lets say i have a list set arr=(x y z e f) I wanna iterate the list with foreach , not I am trying to find example of time based while loop but not having any luck. I'm wondering if it is possible to tell the foreach loop to skip the first line of data. echo "output: $i" Hello all, I'm working on a foreach loop to compare a couple sets of data. Nesting while loop with for loop in bash. Viewed 2k times shell; csh; tcsh; Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company Note that the double quotes around "${arr[@]}" are really important. Instead of iterating until a specific condition is met, the until loop iterates until a condition is no longer true. Remember shellshock, aka bashdoor? #!/bin/csh I'm using a `while(1)` loop to dispaly real-time information about various files on my in my csh script when i tried to use the foreach loop like this: foreach x ( ls ) file. In the tcsh shell, break causes execution to resume after the end of the nearest enclosing foreach or while. When the code is running, as long I'm trying to run a foreach loop within just 1 line of code instead of typing each indivdual command like below; Set n=0 ; foreach txt ( *_*. {1. to reinitialize the. foreach i ($t) echo $i >> /tmp/z. csh, the C shell script; The csh foreach loop syntax is as follows: foreach n ( 1 2 3 4 5 ) #command1 #command2 end However, bash lacks foreach syntax; instead, you can use bash while loop or foreach in csh. I really don't think that line would tolerate spaces, each of the space separated values would be a new element in the array (not a whole line). csh/sh for loop The break and continue loop control commands [1] correspond exactly to their >counterparts in other programming languages. txt) foreach? sed “s/_/-/g” $txt foreach? @ n ++ foreac I have a foreach loop in a csh script and I noticed that it tries to find the files with the pattern $searchpt in the file name. Add a comment | 1 Answer Sorted by: Reset to Nested For loop in shell script. This Maybe you could move those lines into a different file and then source the file from your csh script, like this: foreach envMast ( `seq 4 I am writing a very small csh script which uses a foreach loop to read a list of files, runs the files through a program called 'rdseed', converting them into another file type, and then outputs the new files. txt i want use C shell script to write out while both of the file got different limit. cshrc files) which could point you in the right direction. Without them, the for loop will break up the array by substrings separated by any spaces within the strings instead of by whole string elements within the array. Hi You might find it very trivial but actually don't know how to loop through all sub-directories and their child directories into a csh. The proper way to refer to individual subprocesses inside a script is by PID, and even then, waiting for processes to complete is automatic unless they're explicitly backgrounded by your code (as with a &), or they self-detach (in which case wait won't even work, and the PID given to the shell will be invalidated by the double-fork process used to self-background). This reads the file "myfile. It reads from the file myfile. 2m times. Viewed 2k times shell; csh; tcsh; 1. Asked 15 years, 1 month ago. 4} to output {1. Also note that you can write al as a simple shell script: [ $# != 0 ] && printf "%s\n" "$@" In TCSH : I'm giving two lists containing different files in it. set q=(how now brown cow) echo $q[2] The foreach loop neatly iterates I found that csh was giving me issues splitting the files into their own iteration of $file (it would lump all the files into a single string with EOL's in between! Go figure), so I had If I can give foreach command in a single line, I could easily substitue the target file names to repeat the process. It's: while (arithmetic-expression) body end When csh is interactive, for some reason, that end has to appear on its own on a line. or perl. 4}). bash was easier I believe but here I am, stuck with csh. In addition to the problems they have with single-line scripts, they won't work with make's parallel jobserver support because they do nasty things with file descriptors. instead of foreach i (do stuff for i), we have foreach i j(do stuff for i; do stuff for j) I am working under BASH and TCSH shell environments cheers (3 Replies) That's all. login, which makes the script run faster and avoids dependencies. ) At a wild guess, you've got a . 4} is a zsh operator, extended from csh's {x,y} brace expansion operator now supported by a few other shells, but it's not a POSIX sh operator (until recently, POSIX actually even required echo {1. Unlike source, however, when your exec-ed program ends, the entire process ends. You can use the -X option which will display commands executed in the startup scripts (the . sh script that Robert Gamble showed, and could be written as a shell function (but shell functions didn't exist in the local version of Bourne shell when I first wrote al). (I usually use `find . ${@} Positional arguments. In a foreach loop, is it possible for the loop to go through 2 arguments instead of one i. They might need to run on whatever is installed as /bin/sh, and then there are all the usual pro-standards arguments. I have gotten the following to work: for i in {2. lets say i have a list set arr= (x y z e f) I wanna iterate In bash, code like this will read each line in a file one at a time: while IFS=$'\r' read -r line || [[ -n "$line" ]]; do. ). (This applies only to FOREACH_EXAMPLE1 shows how the foreach command can set a variable to each value, in succession, from an explicit list. This example uses the case statement, which we'll cover later. Shell script: Passing a string as variable to a loop and iterate in all subdirectories and files. For the arithmetic-expression to test on the success of a command, you need { cmd } (spaces are required). I have a foreach loop in a csh script and I noticed that it tries to find the files with the pattern *$searchpt* in the file name. 1. These forms are mostly inspired by the C shell, which was fairly common when zsh was young but has now disappeared. Then I have to pass those list as an array element and then the loop should execute twice as there are only 2 lists. something. csh/sh for loop Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company Another useful trick is the while read loop. done < "to-read-file". In bash scripting, the until loop is similar to the while loop, but with a slightly different syntax. The default value of number is 1. e. Scripts might need a faster shell, a more secure one, a more embedded-style one. foreach xxx ( `grep - Bash iteration statements are simply the repetition of a process within a shell script. Arrays, most of the time, are coupled with loops. (note: Each line must end with a LF (newline) - if cat myfile. instead of foreach i (do stuff for i), we have foreach i j(do stuff for i; do stuff for j) I am working under BASH and TCSH shell environments cheers (3 Replies) You need. csh currently has just few setenvs and I got the setenv working from both csh/bash scripts using the solution from the following post. not for a long-term use. Improve this answer. When used in a nested loop, the until loop can help to automate #!/bin/csh -f foreach line (`cat test. If number is given, break exits from the given number of enclosing loops. Hot Network Questions If you want to write shell scripts use a POSIX-compatible shell. Commented May 16, 2022 at 21:21. The continue Command If you want the loop to step over a particular entry, test whether the iterator matches that entry and use the continue command. (Conversely, set +B (set +o braceexpand) would turn brace extension OFF. Bash is a great shell and I use it interactively, but I don't put bash-isms into my scripts. The big mistake you are making is trying to do text processing in csh (and it wouldn't be much better in a bourne-like shell - less buggy, but still awful). { cmd } in arithmetic expressions resolves to 1 if the Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company From that link, note for example: You can't combine multiline constructs in a csh using semicolons. wc -l -- "${file}" External command that will print the number of lines in ${file} (except when ${file} is -in which POSIXly, you can use IFS= read -r line to read one line off some input, but beware that if you redirect the whole while read loop with the input file on stdin, then commands inside the loop will also have their stdin redirected to the file, so best is to My project environment has both the csh and bash scripts. txt doesn't end with a blank line, that final line will not be processed. cshrc file that's changing the directory. txt, and for each line, tells you what language it thinks is being used. `for` statement in Shell Script in Linux. Any of the two will be suited for what your needs seem to be. I'm confused as I never specified I have a foreach loop in a csh script and I noticed that it tries to find the files with the pattern *$searchpt* in the file name. These iteration statements or loops are very useful when dealing with a list of elements. Iterating Over the output of Commands. get a simpler version of your foreach to work first. Without them, we can’t automate repetitive tasks such as retrieving the contents of a list. It has been widely distributed, beginning with the 2BSD release of the Berkeley Software Distribution (BSD) which Joy first distributed in 1978. Follow If you don't wish to mess with IFS (perhaps for the code within the loop) this might help. The continue command abandons the current spin of the loop. cshrc and . Viewed 1. 0. -name ` for target files) For the purpose of this Hey all, I know cshell is harmful:) but I am using this just “to know” - for educational purposes!. 10} do. But in this cas If you are new to shell scripting, probably abandon tcsh The problem you're seeing is because your "here document" between <<EOT and EOUT is not working inside the foreach loop. or just foreach i (*) This loop structure works well with a built-in concept that csh has of a word list. There is a csh script (say c. file Variable that will iterate over the arguments given in ${@}. break exits from a for, select, while, or until loop in a shell script. So el | The UNIX and Linux Forums Format. However, each datafile includes a header row. Modified 9 years ago. foreach xxx ( `grep - I try to make script in c-shell which is checking if it is called with -g or -h arguments. break [number]. txt value. 7. foreach_example1. variable to 0 inside the foreach loop. 6. Here var is the name of a variable and word1 to wordN are sequences of characters separated by I try to make script in c-shell which is checking if it is called with -g or -h arguments. The versatile Bash for loop does much more than loop around a set number Shell script "for" loop syntax. 226. Iterate over a list of files with spaces. And, unless your job is mandating you to In a foreach loop, is it possible for the loop to go through 2 arguments instead of one i. In csh: How do I redirect the output from a foreach-loop to a pipe? This works but uses a temp file: set tmpfile=/tmp/file Basic structure of a nested while loop in bash scripting Using the until loop for Nested Loops. The for loop operates on lists of items. I would like to run grep for a pattern '`define'. txt`) But on running the above csh script i am getting following output which prints on the basis of space delimiter instead of new line Read user input with spaces in csh Shell Script. The break command terminates the loop >(breaks out of it), while continue causes a jump to the next iteration of the loop, >skipping all the remaining commands in that particular loop cycle. y}, it's not the best way to do loops that increment an integer variable as you end up allocating a list In bash, I know that it is possible to write a for loop in which some loop control variable i iterates over specified integers. The Dazzling for Loop. It increments the iterator and starts the next spin of the loop---assuming the entry you want to skip over isn't the last item in the list. The OP was asking how to iterate over every single line in a file. . I'm confused as I never specified checking for the foreach in csh. 268. Share. exec will replace the running process space with the new process. I've been using the basic code as I want to parse in my foreach, if someone passed an invalid argument, meaning -(anything here, how can I parse invalid argument through the foreach loop? Ask Question Asked 9 years ago. csh) sourced from other csh and bash scripts and c. How to write a setevn/export script that will work in both csh and bash Hey all, I know cshell is harmful:) but I am using this just “to know” - for educational purposes!. txt", one line at a The syntax of while loops in csh is different from that of Bourne-like shells. I've made a tcsh file to save to a file the list of all files/folders in the folder it's run (I'm working on a neuroimaging project, and I'm having the folder RawData containing a number of subjects each having a folder; I've written this file genSubjList. If it is called with some other argument it should simply echo "Wrong argument". The C shell (csh or the improved version, tcsh) is a Unix shell created by Bill Joy while he was a graduate student at University of California, Berkeley in the late 1970s. Edit: This loop will run continiously without any sleep, so the loop condition should be based on loop's start time and current time, not on sleep. Shell script looping directory. how i going to write it in 1 while From that link, note for example: You can't combine multiline constructs in a csh using semicolons. How can I read one line at a time with C shell in unix. Modified 6 years, 3 months ago. ie: if you had declare -a arr=("element 1" "element 2" "element 3"), then for i in ${arr[@]} would mistakenly iterate 6 times since each Hi You might find it very trivial but actually don't know how to loop through all sub-directories and their child directories into a csh. Multiple elements instead of one in bash script for loop. It repeats a set of commands for every item in a list. The problem is that when If you really much continue using csh get a copy of the Anderson's Guide to the Csh (or similar title). – j_b. The pattern works in standalone grep command but fails in for-loop. How would one grep backtick from files in a for-loop. I want to run a loop for specific amount of time, let's say 1 hour. The problem is that when In a foreach loop, is it possible for the loop to go through 2 arguments instead of one i. It is equivalent to the test. Write the whole thing in awk. I'm confused as I never specified for Loops Using Associative Arrays. I’m confused as I never specified checking for the files. For a reduced version of the problem, please first read Update1 below. Even in zsh or other shells that now support {x. Using cut, one would have to either know the number of lines in the file and write that many statements using cut or write a while loop anyway giving you an O(n + n²) time complexity. For example, I can write a bash shell script that prints the integers #!/bin/bash for file in "${@}"; do wc -l -- "${file}" done #!/bin/bash Program that will execute this script. So loop runs for an hour and then ends automatically. or almost any language that isn't sh/bash/ksh/zsh/etc or csh/tcsh. IMHO Korn Shell is better suited for scripting, but this may be personal taste as much as professional opinion. I suggest #!/bin/csh -f. Several forms of complex commands such as loops have alternate forms in zsh. tcsh to save a list of subjects to the file done: Marks the end of the loop. Arguments that you give to the script through command line. instead of foreach i (do stuff for i), we have foreach i j(do stuff for i; do stuff for j) I am working under BASH and TCSH shell environments cheers (3 Replies) If you're confident that it is indeed bash executing your script, you can explicitly turn on brace expansion (expansion of {} expressions) as follows: set -B # same as: set -o braceexpand Make this your script's first command after your shebang. This is sort-of present in bash but not in vanilla posix shells. So you can do this: #!/bin/sh exec /path/to/csh/script but you can't do this: #!/bin/sh exec /path/to/csh/script I want to parse in my foreach, if someone passed an invalid argument, meaning -(anything here, how can I parse invalid argument through the foreach loop? Ask Question Asked 9 years ago. break is a special built-in shell command. These alternate forms act exactly like the normal forms, they're just a The closest you can come to sourcing a script with a different executor than your original script is to use exec. Accessing multi-word directory names in a shell script. It is a modle of good technical writing and will make you a true power user of csh but if you get really good with csh, you'll reach a point where you'll find there are tasks you cannot do using the limited syntax of csh, you'll need to use other tools to achieve your goal How would one grep backtick from files in a for-loop. The break and continue loop control commands [1] correspond exactly to their >counterparts in other programming languages.