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Tag: linux

Windows C Runtime toupper slow when locale set

I’m diagnosing an edge case in a cross platform (Windows and Linux) application where toupper is substantially slower on Windows. I’m assuming this is the same for tolower as well. Originally I tested this with a simple C program on each without locale information set or even including the header …

Double Free – crash or no crash

Can someone explain me why freeing a twice in a row causes a crash, but freeing a first, then b, and then a again does not crash? I know that a free will insert the heap chunk in a double linked free list. Freeing twice would insert the same chunk twice in the free list. But why is the crash

how to tell the version number of dash?

I have a dash shell installed as /bin/dash. I checked the manual of dash, which is the same as the POSIX shell manual, and there is nothing there to tell the version of the shell. dash –version does not work. How to tell the version number of dash I have?? Added: some people are pointing me to Ubuntu co…

Behavior of fgetc() function in C

I am looking for an easy way to manage file opening and closing in x86-64 assembly on linux. I thought the easiest way would be to write a c file containing functions that I could call without having to worry about stability. So I wrote this function : And then I read the port like so: Where PORT.p is a

Replace line with double quotes

I want to replace a line with double quotes on OpenBox startup, like: with I use this command, but it does not work: It gives me this error: Answer The ampersand in the replacement string recalls the pattern in the search string. So you can just do this: Also, you can use single quotes on the outside, and dou…

Linux: Recv randomly returns zero

I wrote a simple TCP network library with epoll for linux. In one of my tests, I want to test the throughput of the library. I send 2000000 msgs of 500 bytes. The binded socket randomly returns zero on a recv after 800000 or more msgs have been received. Other times, all messages are received. What would caus…

Php.ini changes are not taken on Linux Bitnami Ubuntu

I am using a LAMP stack from Bitnami with Ubuntu. I am trying to increase post_max_size in file php.ini. I changed these values: Then reset with sudo /opt/bitnami/ctlscript.sh restart php-fpm (taken from the Bitnami documentation). No changes take effect. I have tried removing all the text from php.ini. I get…