XSetFont - GC convenience routines
int XSetFont(Display *display, GC gc, Font
    font);
  - display
- Specifies the connection to the X server.
- font
- Specifies the font.
- gc
- Specifies the GC.
The XSetFont function sets the current font in the specified GC.XSetFont can generate BadAlloc, BadFont, and
    BadGC errors.
  - BadAlloc
- The server failed to allocate the requested resource or server
    memory.
- BadFont
- A value for a Font or GContext argument does not name a defined Font.
- BadGC
- A value for a GContext argument does not name a defined GContext.
XCreateGC(3), XQueryBestSize(3), XSetArcMode(3), XSetClipOrigin(3),
  XSetFillStyle(3), XSetLineAttributes(3), XSetState(3), XSetTile(3)
Xlib - C Language X Interface