A utility for printing out the name and windowId for every current window. Use in conjunction with 'screencapture -l' to automate screenshots.

get_window_list.mm

// GetWindowList
// A utility for printing out the name and windowId for every current window.
// Use in conjunction with 'screencapture -l' to automate screenshots.

// compile with gcc thusly:
// gcc -framework carbon -framework foundation -framework cocoa -x objective-c -std=c99 GetWindowList.c -o GetWindowList

#include <Carbon/Carbon.h>
#import <objc/Object.h>
#import <Foundation/Foundation.h>
#import <Cocoa/Cocoa.h>

int main(int argc, char **argv) {
    CFArrayRef windowArray = CGWindowListCopyWindowInfo(kCGWindowListOptionOnScreenOnly, kCGNullWindowID);
    NSMutableArray *windowsInMap = [NSMutableArray arrayWithCapacity:64];
    NSArray*  windows = (NSArray*)CGWindowListCopyWindowInfo(kCGWindowListOptionOnScreenOnly, kCGNullWindowID);
    NSUInteger count = [windows count];
    for (NSUInteger i = 0; i < count; i++)
    {
        NSDictionary*   nswindowsdescription = [windows objectAtIndex:i];
        NSNumber* windowid = (NSNumber*)[nswindowsdescription objectForKey:@"kCGWindowNumber"];
        NSString* windowName = (NSString*)[nswindowsdescription objectForKey:@"kCGWindowOwnerName"];
        if(windowid)
        {
            printf("%s:%s\n", [windowName UTF8String], [[windowid stringValue] UTF8String]);
        }
    }
    CFRelease(windowArray);
}