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	Update example in farbfeld.5 - farbfeld - suckless image format with conversion…
	git clone git://git.suckless.org/farbfeld
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	---
	commit b52f376a0f18db0dc8b2c8707cf3f41d32fd9a10
	parent ac1630a81790f5db946d7091e08b758714c8cd19
	Author: FRIGN <[email protected]>
	Date: Tue, 5 Jan 2016 11:10:39 +0100

	Update example in farbfeld.5

	We were close to a full program anyway, so I just completed the code so
	you can study and run it easily.

	Diffstat:
	M farbfeld.5 \| 87 +++++++++++++++++------------…

	1 file changed, 48 insertions(+), 39 deletions(-)
	---
	diff --git a/farbfeld.5 b/farbfeld.5
	@@ -45,8 +45,8 @@ and inherent complexity involved in handling common image for…
	(PNG, JPEG, GIF,...), having to rely on bloated libraries not being able
	to focus on the task at hand for a given problem.
	.Sh EXAMPLES
	-Below is an example for a color inverter. No external libraries other
	-than libc are needed to read the image data:
	+Below is an example for a color inverter usable in a pipeline. No external
	+libraries other than libc are needed to handle the image data:
	.Bd -literal -offset left
	#include <arpa/inet.h>

	@@ -55,49 +55,58 @@ than libc are needed to read the image data:
	#include <stdlib.h>
	#include <string.h>

	-(...)
	+int
	+main(int argc, char *argv[])
	+{
	+ uint32_t width, height, i, j, k;
	+ uint16_t rgba[4];
	+ uint8_t hdr[strlen("farbfeld") + 2 * sizeof(uint32_t)];

	-uint32_t width, height, i, j, k;
	-uint16_t rgba[4];
	-uint8_t hdr[strlen("farbfeld") + 2 * sizeof(uint32_t)];
	+ if (argc > 1) {
	+ fprintf(stderr, "usage: %s\\n", argv[0]);
	+ exit(1);
	+ }

	-if (fread(hdr, 1, sizeof(hdr), infile) != sizeof(hdr)) {
	- fprintf(stderr, "incomplete header\\n");
	- exit(1);
	-}
	-if (memcmp("farbfeld", hdr, strlen("farbfeld"))) {
	- fprintf(stderr, "invalid magic\\n");
	- exit(1);
	-}
	-width = ntohl(((uint32_t )(hdr + 8)));
	-height = ntohl(((uint32_t )(hdr + 12)));
	+ if (fread(hdr, 1, sizeof(hdr), stdin) != sizeof(hdr)) {
	+ fprintf(stderr, "incomplete header\\n");
	+ exit(1);
	+ }
	+ if (memcmp("farbfeld", hdr, strlen("farbfeld"))) {
	+ fprintf(stderr, "invalid magic\\n");
	+ exit(1);
	+ }
	+ width = ntohl(((uint32_t )(hdr + 8)));
	+ height = ntohl(((uint32_t )(hdr + 12)));

	-if (fwrite(hdr, 1, sizeof(hdr), outfile) != sizeof(hdr)) {
	- fprintf(stderr, "write error\\n");
	- exit(1);
	-}
	+ if (fwrite(hdr, 1, sizeof(hdr), stdout) != sizeof(hdr)) {
	+ fprintf(stderr, "write error\\n");
	+ exit(1);
	+ }

	-for (i = 0; i < height; i++) {
	- for (j = 0; j < width; j++) {
	- if (fread(rgba, sizeof(uint16_t), 4, infile) != 4) {
	- fprintf(stderr, "unexpected EOF\\n");
	- exit(1);
	- }
	- for (k = 0; k < 4; k++) {
	- rgba[k] = ntohs(rgba[k]);
	- }
	+ for (i = 0; i < height; i++) {
	+ for (j = 0; j < width; j++) {
	+ if (fread(rgba, sizeof(uint16_t), 4,
	+ stdin) != 4) {
	+ fprintf(stderr, "unexpected EOF\\n");
	+ exit(1);
	+ }
	+ for (k = 0; k < 4; k++) {
	+ rgba[k] = ntohs(rgba[k]);
	+ }

	- /* invert colors */
	- rgba[0] = 65535 - rgba[0];
	- rgba[1] = 65535 - rgba[1];
	- rgba[2] = 65535 - rgba[2];
	+ /* invert colors */
	+ rgba[0] = 65535 - rgba[0];
	+ rgba[1] = 65535 - rgba[1];
	+ rgba[2] = 65535 - rgba[2];

	- for (k = 0; k < 4; k++) {
	- rgba[k] = htons(rgba[k]);
	- }
	- if (fwrite(rgba, sizeof(uint16_t), 4, outfile) != 4) {
	- fprintf(stderr, "write error\\n");
	- exit(1);
	+ for (k = 0; k < 4; k++) {
	+ rgba[k] = htons(rgba[k]);
	+ }
	+ if (fwrite(rgba, sizeof(uint16_t), 4,
	+ stdout) != 4) {
	+ fprintf(stderr, "write error\\n");
	+ exit(1);
	+ }
	}
	}
	}