System calls are operating system functions, like on UNIX, the malloc() function is built on top of the sbrk() system call (for resizing process memory space). Libraries are just application code that’s not part of the operating system and will often be available on more than one OS. They’re basically the same as function calls … Read more
NAME putenv – change or add an environment variable SYNOPSIS #include <stdlib.h> int putenv(char *string); DESCRIPTION The putenv() function adds or changes the value of environment variables. The argument string is of the form name=value. If name does not already exist in the environment, then string is added to the environment. If name does exist, … Read more
If you use the “normal” libstdc++ shipped with g++, its documentation is available online here. Most Linux distributions make it also available offline as a particular package; for Debian-derived distros, for example, it’s libstdc++-6-<version>-doc (e.g. on my Ubuntu machine I have libstdc++-6-4.4-doc installed). In general the documentation will be put somewhere like /usr/share/doc/libstdc++-6-4.4-doc. This about … Read more
Square Brackets [ ] The square brackets ( [ ] ) indicate that the enclosed element (parameter, value, or information) is optional. You can choose one or more items or no items. Do not type the square brackets themselves in the command line. Example: [global options], [source arguments], [destination arguments] Angle Brackets < > The … Read more
It’s the man page section. From memory, section 1 is user programs, 2 is system calls, and 3 is standard C library calls, and 5 is file formats. Wikipedia has the full explanation here.
It’s the section that the man page for the command is assigned to. These are split as General commands System calls C library functions Special files (usually devices, those found in /dev) and drivers File formats and conventions Games and screensavers Miscellanea System administration commands and daemons Original descriptions of each section can be seen … Read more