I have a problem with some read/write functions.
I have a .bin file which contains a lot of structures as follows:
What I have to do is read the file, firstly one structure by one, and then all the file at once and change the value if notamedia is less than 3. I'm using read() and lseek(), but I'm very loss . Somebody can give me a hand in developing the code. I believe is not too big.
Thanks in advance for the help
Last edited by pludi; 11-12-2009 at 04:43 AM..
Reason: code tags, please...
Hi!
All!
I am wirting a shell script in which i want to read one line
at a time from the file and write it simultaneouly to other file one line at a time.
Please let me know about some shell utility which can help me out.
Thanx.
If further clarifications are needed then please let me know... (2 Replies)
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I am a Newbie in ksh Unix Script.
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hi everybody,
i am working in device drivers.As a beginner to this field ,i dont know how to read or write device files. Will copy_to_user and copy_from_user help me?
I have created a device file using mknod command .Can anybody help me in this regard :confused
thanks in advance
sriram (1 Reply)
Hi
I need some help on SED command
I am writing a shell script which does the following:
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I need to find all the files that have group Read or Write permission or files that have user write permission.
This is what I have so far:
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Hi,
We have smb client running on two of the linux boxes and smb server on another linux system. During a backup operation which uses smb, read of a file was allowed while write to the same file was going on.Also simultaneous writes to the same file were allowed.Following are the settings in the... (1 Reply)
Need help reading file last modified date in format:
Filename (relative path);YYYYMMDDHHMMSS
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Checked this command but does not work:
Getting the Last Modification Timestamp of a File with Stat
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Dear Friends,
I am looking for a shell script to merge input files into one file .. here is my idea:
1st paramter would be outfile file (all input files content)
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Dears.
kindly guide !!!
I have data, which is delimited by | .
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Discussion started by: sadique.manzar
3 Replies
LEARN ABOUT ULTRIX
atan2
sin(3m)sin(3m)Name
sin, cos, tan, asin, acos, atan, atan2 - trigonometric functions and their inverses
Syntax
#include <math.h>
double sin(x)
double x;
float fsin(x)
float x;
double cos(x)
double x;
float fcos(x)
float x;
double tan(x)
double x;
float ftan(x)
float x;
double asin(x)
double x;
float fasin(x)
float x;
double acos(x)
double x;
float facos(x)
float x;
double atan(x)
double x;
float fatan(x)
float x;
double atan2(y,x)
double y,x;
float fatan2(y,x)
float y,x;
Description
The and functions return trigonometric functions of radian arguments x for double data types.
The and functions return trigonometric functions for float data types.
The and functions return the arc sine in the range -pi/2 to pi/2 for double and float data types, respectively.
The and functions return the arc cosine in the range 0 to pi for double and float data types, respectively.
The and functions return the arc tangent in the range -pi/2 to pi/2 for double and float data types, respectively.
The and functions return the arc tangent of y/x in the range -pi to using the signs of both arguments to determine the quadrant of the
return value for double and float data types, respectively.
Error (due to roundoff)
When P stands for the number stored in the computer in place of pi = 3.14159 26535 89793 23846 26433 ... . and "trig" stands for one of
"sin", "cos" or "tan", then the expression "trig(x)" in a program actually produces an approximation to trig(x*pi/P), and "atrig(x)"
approximates (P/pi)*atrig(x). The approximations are close.
P differs from pi by a fraction of an ulp; the difference is apparent only if the argument x is huge, and even then the difference is
likely to be swamped by the uncertainty in x. Every trigonometric identity that does not involve pi explicitly is satisfied equally well
regardless of whether P = pi. For example, sin(x)**2+cos(x)**2 = 1 and sin(2x) = 2sin(x)cos(x) to within a few ulps regardless of how big
x is. Therefore, the difference between P and pi is unlikely to effect scientific and engineering computations.
Return Values
All the double functions return NaN if NaN is passed in.
If |x| > 1 then (x) and (x) will return the default quiet NaN.
The function defines (0,0) = NaN.
See Alsohypot(3m), math(3m), sqrt(3m)
RISC sin(3m)