userspace/cat.c


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#include <stdio.h>
#include <stdlib.h>

int main(int argc, char **argv)
{   
	// Input (default stdin)
	FILE *in=stdin;

	// Output
	FILE *out=stdout;

	// In case a Filename was supplied
	if(argc>1){
		char buf[256];

		// Relative Path
		if(argv[1][0]!='/')
		{
		    sprintf(buf,"%s/%s",getenv("PWD"),argv[1]);
		    in=fopen(buf,"r");
		}

		// Absolute Path
		else
		{
		    in=fopen(argv[1],"r");
		}
	}

	char buf[256];

	while(1)
	{
		int l=fread(buf,1,255,in);
		buf[l]=0;
		if(l==0)break;
		fwrite(buf,1,l,out);
	}

	return EXIT_SUCCESS;
}