erand48_r - Linux
Overview
erand48_r is a C library function that generates a random number using the erand48 family of pseudorandom number generators. It is designed to be reentrant and thread-safe, making it suitable for use in multithreaded applications.
Syntax
int erand48_r(struct drand48_data *buf, double *result);
Parameters:
- buf: Pointer to a
drand48_data
structure holding the internal state of the random number generator. - result: Pointer to the variable to store the generated random number.
Return Value:
The function returns 0 on success, or -1 if an error occurs.
Options/Flags
None.
Examples
Simple Usage:
#include <stdlib.h>
int main() {
struct drand48_data buf;
srand48_r(1234, &buf);
double r = erand48_r(&buf);
printf("Random number: %f\n", r);
return 0;
}
Common Issues
Incorrect Initialization:
- Ensure that you initialize the
drand48_data
structure usingsrand48_r
before callingerand48_r
.
Thread Safety:
- The
erand48_r
function is reentrant and can be safely used in multithreaded applications. However, each thread should use its owndrand48_data
structure.
Integration
Generating Random Data:
erand48_r
can be used in scripts or programs that require random data, such as simulations, testing, and games.
Related Commands
- rand: Generates a random integer.
- srand: Initializes the random number generator.
- drand48: Generates a double-precision random number.
- srand48_r: Initializes the
drand48_data
structure for the erand48 family of random number generators.