getconf command examples

getconf – get configuration values

The following example illustrates the value of {NGROUPS_MAX}:

getconf NGROUPS_MAX

The following example illustrates the value of {NAME_MAX} for a specific directory:

getconf NAME_MAX /usr

The following example shows how to deal more carefully with results that might be unspecified:

if value=$(getconf PATH_MAX /usr); then
    if [ "$value" = "undefined" ]; then
        echo PATH_MAX in /usr is infinite.
    else
        echo PATH_MAX in /usr is $value.
    fi
else
    echo Error in getconf.
fi

Note that:

sysconf(_SC_POSIX_C_BIND);

and:

system("getconf POSIX2_C_BIND");

in a C program could give different answers. The sysconf() call supplies a value that corresponds to the conditions when the program was either compiled or executed, depending on the implementation; the system() call to getconf always supplies a value corresponding to conditions when the program is executed.