The csh shell has never been known for its extensive ability to manipulate file handles in the redirection process. You can redirect both standard output and error to a file with: xxx >& filename but that’s not quite what you were after, redirecting standard error to the current standard output. However, if your underlying operating … Read more
sed can use any separator instead of / in the s command. Just use something that is not encountered in your paths: s+AAA+BBB+ and so on. Alternatively (and if you don’t want to guess), you can pre-process your path with sed to escape the slashes: pwdesc=$(echo $PWD | sed ‘s_/_\\/_g’) and then do what you … Read more
With awk: awk ‘{for(i=1;i<=NF;i++) if ($i==”–pe_cnt”) print $(i+1)}’ inputFile Basically loop over each word of the line. When you find the first you are looking for, grab the next word and print it. With grep: grep -oP “(?<=–pe_cnt )[^ ]+” inputFile
Try with: xargs –show-limits </dev/null Your environment variables take up 2446 bytes POSIX upper limit on argument length (this system): 2092658 POSIX smallest allowable upper limit on argument length (all systems): 4096 Maximum length of command we could actually use: 2090212 Size of command buffer we are actually using: 131072 There is no limit per … Read more
It does affect, at least bash in my environment, but in very unpleasant way. See these codes. First a.sh: #!/bin/sh echo “First echo” read y echo “$y” echo “That’s all.” b.sh: #!/bin/sh echo “First echo” read y echo “Inserted” echo “$y” # echo “That’s all.” Do $ cp a.sh run.sh $ ./run.sh $ # open … Read more
I have good experience with the following code. It doesn’t require any special user permissions: import resource, sys resource.setrlimit(resource.RLIMIT_STACK, (2**29,-1)) sys.setrecursionlimit(10**6) It does however not seem to work with pypy. If resource.setrlimit doesn’t work, you can also try using threads: sys.setrecursionlimit(10**6) import threading threading.stack_size(2**26) threading.Thread(target=main).start()
There are three approaches to finding the name of the current shell’s executable: Please note that all three approaches can be fooled if the executable of the shell is /bin/sh, but it’s really a renamed bash, for example (which frequently happens). Thus your second question of whether ps output will do is answered with “not … Read more
I had this problem in a program I wrote a year ago — turns out the answer is rather complicated. You’ll need to use nohup as well as output redirection, as explained in the wikipedia artcle on nohup, copied here for your convenience. Nohuping backgrounded jobs is for example useful when logged in via SSH, … Read more
Use the “dot space script” calling syntax. For example, here’s how to do it using the full path to a script: . /path/to/set_env_vars.sh And here’s how to do it if you’re in the same directory as the script: . set_env_vars.sh These execute the script under the current shell instead of loading another one (which is … Read more