BSWAP(3) Linux Programmer's Manual BSWAP(3)NAME
bswap_16, bswap_32, bswap_64 - reverse order of bytes
SYNOPSIS
#include <byteswap.h>
bswap_16(x);
bswap_32(x);
bswap_64(x);
DESCRIPTION
These macros return a value in which the order of the bytes in their 2-, 4-, or 8-byte arguments is reversed.
RETURN VALUE
These macros return the value of their argument with the bytes reversed.
ERRORS
These macros always succeed.
CONFORMING TO
These macros are GNU extensions.
EXAMPLE
The program below swaps the bytes of the 8-byte integer supplied as its command-line argument. The following shell session demonstrates
the use of the program:
$ ./a.out 0x0123456789abcdef
0x123456789abcdef ==> 0xefcdab8967452301
Program source
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <inttypes.h>
#include <byteswap.h>
int
main(int argc, char *argv[])
{
uint64_t x;
if (argc != 2) {
fprintf(stderr, "Usage: %s <num>
", argv[0]);
exit(EXIT_FAILURE);
}
x = strtoul(argv[1], NULL, 0);
printf("0x%" PRIx64 " ==> 0x%" PRIx64 "
", x, bswap_64(x));
exit(EXIT_SUCCESS);
}
SEE ALSO byteorder(3), endian(3)Linux 2019-03-06 BSWAP(3)
Check Out this Related Man Page
BSWAP(3) Linux Programmer's Manual BSWAP(3)NAME
bswap_16, bswap_32, bswap_64 - reverse order of bytes
SYNOPSIS
#include <byteswap.h>
bswap_16(x);
bswap_32(x);
bswap_64(x);
DESCRIPTION
These macros return a value in which the order of the bytes in their 2-, 4-, or 8-byte arguments is reversed.
RETURN VALUE
These macros return the value of their argument with the bytes reversed.
ERRORS
These macros always succeed.
CONFORMING TO
These macros are GNU extensions.
EXAMPLE
The program below swaps the bytes of the 8-byte integer supplied as its command-line argument. The following shell session demonstrates
the use of the program:
$ ./a.out 0x0123456789abcdef
0x123456789abcdef ==> 0xefcdab8967452301
Program source
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <inttypes.h>
#include <byteswap.h>
int
main(int argc, char *argv[])
{
uint64_t x;
if (argc != 2) {
fprintf(stderr, "Usage: %s <num>
", argv[0]);
exit(EXIT_FAILURE);
}
x = strtoul(argv[1], NULL, 0);
printf("0x%" PRIx64 " ==> 0x%" PRIx64 "
", x, bswap_64(x));
exit(EXIT_SUCCESS);
}
SEE ALSO byteorder(3), endian(3)Linux 2019-03-06 BSWAP(3)
i found this code in the book but was unable to execute it.
/*myecho -- echo command line arguments */
main(int argc, char **argv)
{
while(--argc > 0)
printf("%s ", *++argv);
printf("\n");
}
this is another program that would invoke the one above
char * const argin =... (5 Replies)
Hi
I have a program
int main(int srgc, char *argv)
{
for(int i=1; i<50; i++)
{
system("dd if=/dev/zero of=file$i bs=1024 count=$i");
}
return 0;
}
My doubt is how to use the "$i" value inside C code
Please help (2 Replies)
Use and complete the template provided. The entire template must be completed. If you don't, your post may be deleted!
1. The problem statement, all variables and given/known data:
First, create a "hello world" program that prints "Hello World". But NOW, instead use argc to verify that a... (9 Replies)