NAME

unistd − file header for symbolic constants

SYNOPSIS

#include <unistd.h>

DESCRIPTION

The header file <unistd.h> lists the symbolic constants and structures not already defined or declared in some other header file. 

/∗ Symbolic constants for the "access" routine: ∗/

#define R_OK4/∗Test for Read permission ∗/
#define W_OK2/∗Test for Write permission ∗/
#define X_OK1/∗Test for eXecute permission ∗/
#define F_OK0/∗Test for existence of File ∗/
#define F_ULOCK0 /∗Unlock a previously locked region ∗/
#define F_LOCK1 /∗Lock a region for exclusive use ∗/
#define F_TLOCK2 /∗Test and lock a region for exclusive use ∗/
#define F_TEST3 /∗Test a region for other processes locks ∗/
/∗Symbolic constants for the "lseek" routine: ∗/
#define SEEK_SET0 /∗ Set file pointer to "offset" ∗/
#define SEEK_CUR1 /∗ Set file pointer to current plus "offset" ∗/
#define SEEK_END2 /∗ Set file pointer to EOF plus "offset" ∗/
/∗Pathnames:∗/
#define GF_PATH/etc/group /∗Pathname of the group file ∗/
#define PF_PATH/etc/passwd /∗Pathname of the passwd file ∗/

September 02, 1992