04-24-2011
Quote:
Originally Posted by
laopi
Hi,
I had a head file, looks like
#define MIN_NUM 10
#define MAX_NUM 10
is there any way to get "MAX_NUM" from 10?
thanks.
peter
Hi Peter,
A preprocessor directive such as you see "#define" or "#include" is translated by the preprocessor (cpp) before the compiler gets its hands dirty with the code. For example if you write,
#define NUM 5
Then every instance of NUM gets replaced by "5" before the code is compiled. The compiler knows nothing about what NUM is so you cannot use a logic to get NUM from 5.
My question is why would you want NUM which is a variable from 5 which is constant. You can only do the reverse that is get the constant from a variable.
Thanks and Regards,
Gaurav.
8 More Discussions You Might Find Interesting
1. Programming
in the header file orville.h, outside of the #ifdef #endif , there is the following
#define JOB_CONTROL /* support job-control */
As you can see, the JOB_CONTROL macro has no value associated with it. Here is what I go when I ran grep on the entire source code.
$ grep -iR... (6 Replies)
Discussion started by: frequency8
6 Replies
2. UNIX for Dummies Questions & Answers
Hi friends,
I am not sure if perl questions can be raised here. :rolleyes:
But I have a doubt if there is a way to do "#define" in perl, like in C.
Does anyone know if it is feasible (without CPAN modules)?
Thanks,
Srini (7 Replies)
Discussion started by: srinivasan_85
7 Replies
3. Programming
Hello!!
I need to do some performance test using a very big matrix (bi-dimensional array) but I have problems with this.
Is there any limitation in declarations? because if I do this:
int matriz;
It just don't work... it compiles but when i run the program it just closes.
Where can i... (4 Replies)
Discussion started by: Sandia_man
4 Replies
4. Shell Programming and Scripting
Hello,
I would like to define a variable based on another variable:
a=5
b$a=100
This does not work. What is the right way to do it?
Thanks
---------- Post updated at 07:37 PM ---------- Previous update was at 07:33 PM ----------
Found my answer with the search function (did not... (0 Replies)
Discussion started by: jolecanard
0 Replies
5. Programming
Hello,
I would like to conditionaly comment in my code source some fields from arrays. So I use the property ## from the #define definition.
my code:
...
#define slet /##*
#define etsl *##/
...
const T_SVT_ADLL_A653_DESC A_DESC =
{
{ slet qwerty etsl SLICING,... (3 Replies)
Discussion started by: cypleen
3 Replies
6. Programming
if i do this in C
#define NUM 1234512345
then how come i cant print it out using
int main(int argc, char **argv) {
printf("%d\n", NUM);
return 0;
}
well the result is -1219236538, why isnt it 1234512345 ? (7 Replies)
Discussion started by: omega666
7 Replies
7. Programming
Hey everyone. So I'm looking at a few C programming resources, and it seems, by convention how you should write and define a function, is first declare it's existence before your main...then call it somewhere in your main, and then define after, at the end of the program? Is this necessary? I mean... (7 Replies)
Discussion started by: Lost in Cyberia
7 Replies
8. Shell Programming and Scripting
Hi,
I just define the variable in script and use those script in another script but the variable not recognize.
test1.sh
#!/bin/bash
DB="test_db"
USR="test_user"
PWD="test_pwd"
HST="24.254.87.12"
test2.sh
#!/bin/bash
./test1.sh
mysql -u $USR -p $PWD -h $HST... (2 Replies)
Discussion started by: fspalero
2 Replies
LEARN ABOUT V7
traceroute
TRACEROUTE(1) User Commands TRACEROUTE(1)
NAME
traceroute - Trace the route to a host
SYNOPSIS
traceroute [OPTION...] HOST
DESCRIPTION
Print the route packets trace to network host.
-f, --first-hop=NUM
Set initial hop distance, that is the time-to-live.
-g, --gateways=GATES
List of gateways for loose source routing.
-I, --icmp
Use ICMP ECHO as probe.
-m, --max-hop=NUM
Set maximal hop count (default is 64).
-M, --type=METHOD
Use METHOD (icmp or udp) for traceroute operations, defaulting to udp.
-p, --port=PORT
Use destination PORT port (default is 33434).
-q, --tries=NUM
Send NUM probe packets per hop (default is 3).
--resolve-hostnames
Resolve hostnames.
-t, --tos=NUM
Set type of service (TOS) to NUM.
-w, --wait=NUM
Wait NUM seconds for response (default is 3).
-?, --help
Give this help list.
--usage
Give a short usage message.
-V, --version
Print program version.
GNU inetutils 2015-05-15 TRACEROUTE(1)