Search Path (The C Preprocessor)

Abstraction: GCC C preprocessor header include search path rules

Key points:

• Quote-form #include "file" searches first relative to the current file's directory, then the standard system directories
• Angle-bracket form #include <file> searches only standard system directories by default
• -I dir flag adds a directory to the front of the search path for both forms
• -iquote and -isystem provide separate control over quote-form and system-header search paths
• cpp -v /dev/null -o /dev/null prints the actual search path list for a given GCC installation
• -nostdinc suppresses all default system header directories, useful for OS kernels or bare-metal code

Connections: Gcc · C Programming · C Preprocessor

Source: http://gcc.gnu.org/onlinedocs/cpp/Search-Path.html