I think the error occurs if the input encoding of the file is different from the preferred encoding of your environment. Example: in is UTF-8 $ LANG=de_DE.UTF-8 sed ‘s/.*| //’ < in X Y $ LANG=de_DE.iso88591 sed ‘s/.*| //’ < in X Y UTF-8 can safely be interpreted as ISO-8859-1, you’ll get strange characters but … Read more
I solved my problem a few months ago. Here’s the solution I used. The standard packet-sending API (sock_create, connect, …) cannot be used in a few contexts (interruptions). Using it in the wrong place leads to a KP. The netpoll API is more “low-level” and works in every context. However, there are several conditions : … Read more
You’re running into one surprising difference between i386 and x86_64: they don’t use the same system call mechanism. The correct code is: movq $60, %rax movq $2, %rdi ; not %rbx! syscall Interrupt 0x80 always invokes 32-bit system calls. It’s used to allow 32-bit applications to run on 64-bit systems. For the purposes of learning, … Read more
This pre-commit hook will do the file size check: .git/hooks/pre-commit #!/bin/sh hard_limit=$(git config hooks.filesizehardlimit) soft_limit=$(git config hooks.filesizesoftlimit) : ${hard_limit:=10000000} : ${soft_limit:=500000} list_new_or_modified_files() { git diff –staged –name-status|sed -e ‘/^D/ d; /^D/! s/.\s\+//’ } unmunge() { local result=”${1#\”}” result=”${result%\”}” env echo -e “$result” } check_file_size() { n=0 while read -r munged_filename do f=”$(unmunge “$munged_filename”)” h=$(git ls-files … Read more
In general, you can only influence a process’s environment variables at the time the process starts up. If you need to communicate a change to a running process, the environment isn’t the right tool. However, this question has some answers that suggest ways to overcome this limitation. Edited to add in light of discussion in … Read more
Use parameter expansion. ${#chars} is the number of possible characters, % is the modulo operator. ${chars:offset:length} selects the character(s) at position offset, i.e. 0 – length($chars) in our case. chars=abcd1234ABCD for i in {1..8} ; do echo -n “${chars:RANDOM%${#chars}:1}” done echo
Is there a way to force the old behavior? Yes. You can use this option -Wl,–disable-new-dtags to tell the new linker to use the old behavior, i.e. RPATH. Is it possible to tell the old version of linker to produce the new output (i.e. RUNPATH instead of RPATH)? Yes. Use -Wl,–enable-new-dtags to tell the old … Read more
For a joinable (i.e NOT detached) pthread you could use pthread_kill like this: int ret = pthread_kill(YOUR_PTHREAD_ID, 0); If you get a ESRCH value, it might be the case that your thread is dead. However this doesn’t apply to a detached pthreads because after it has ended its thread ID can be reused for another … Read more
This depends in part on your operating system. There is however no limit on a specific port. There is a limit on the number of concurrent connections however, typically limited by the number of file descriptors the kernel supports (eg 2048). The thing to remember is that a TCP connection is unique and a connection … Read more
Another option is to use the prlimit command (from the util-linux package). For example if you want to set the maximum number of open files for a running process to 4096: prlimit -n4096 -p pid_of_process