I need some help with C programming in Linux

Hello, I am using some functions that on error se some value to the errno variable, but I don't know how I can get the value of this variable. thanks.-

how do i included <errno.h>?

>>2
sry dno pls tel

ON ERROR GOTO <linenum> OR GTFO

http://www.cs.cf.ac.uk/Dave/C/subsection2_18_3_3.html

Pussies.

>>1
#include <errno.h>

if (errno == ...) {perror("You fail etc");}

#include <string.h>
#include <errno.h>

fprintf(stderr, "%s\n", strerror(errno));

>>6 those errno.h
i thought u were writing include emo.h XD

>>8
Me too!

>>9
Me too!

>>10
Me too!

>>11
Me too!

>>9
>>10
>>11
>>12

I didnt.

>>13
I did.

sage

age

sex

wow global variables. that's so retarded.

>>18

sage for retarded statement

go learn to think for yourself instead of what your professors cram down your throat

>>19
True. Most things a language provides have their use, and you can abuse every single feature. You shouldn't avoid things that could be abused or failed; you should be learn to use the right tool for every time and tell when something is a good or a bad idea.

>>20
Untrue.  The "auto" keyword in C has NO use.

>>21
the "auto" keyword is not 'most things' the C language provides.

people who use global variables, goto, or operator overloading have failed at life.

>>23

Translation: "John Carmack, the Nethack programmers, and anyone who ever wanted to write something as simple as string concatenation or making complex number arithmetic not-a-coding-eyesore have failed at life."

Which also translates to "I have no fucking idea what I'm talking about because I critique code more than I have ever written any of it."

>>23
people who replace global variables with things like passing extra arguments to every function, or some object that contains config settings, etc. and then act like this method is superior have not only failed at life but have shit all over it.

>>24-25
Agreement

>>23
You haven't done much, right? Or if you did, you like suffering, right?

>>23
Next you'll try to tell us how great Java is

>>18
Untrue. "errno" is actually a thread-local variable, not a global one. Check its definition on your average linux system and you'll likely find that it's something like (*__errno_location()) or some such, which results in getting it from the thread-specific storage area.

>>23 for pres- professor

>>27
Sun-certified professionals can rapidly establish credibility, resulting in peer recognition and professional advancement. As one recent Sun-certified professional said, "Certification helped cement my position in the Java technology community."

>>30"Certification helped cement my position in the Java technology community and we can all sleep with the fishes in the bottom of the sea."
Fixd!

"Certification helped cement my position in the Java technology community."
Which means it's worthless :D

:D

#include <errno.h>
#define errno 0

>>34
/usr/include/errno.h:46:1: warning: this is the location of the previous definition

>>34
Wow, this is a great idea which I will promptly use the next time I have to deal with any sort of error checking.

Thanks Anon, you're a lifesaver.

Hi, I can spam /prog/ too, you faggot.

Also, smoke weed everyday.

my farts burn my anus
it hurts
in a good way

Bringing /prog/ back to its people
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