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/* Do not use this as the basis of your own libc.
* The code is probably suboptimal or wonky, as I
* had no prior experience with this, but instead
* just fiddled with the code until it worked.
*/
#include<stdio.h>
#define STDOUT 1
#define SYS_WRITE 4
int simple_print(const char *msg, const long bufsize) {
int count;
long total_written = 0;
while(total_written < bufsize) {
asm(
"int $0x80\n\t"
: "=a"(count)
: "0"(SYS_WRITE), "b"(STDOUT), "c"(msg+total_written), "d"(bufsize-total_written)
:);
if(count == 0) {
return 1;
}
total_written += count;
}
return 0;
}
int simple_strlen(const char *str) {
int len = 0;
while(str[len] != '\0') {
len++;
}
return len;
}
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