getfsent(3)

✨ getfsent(3) — the fstab whisperer ✨

okay bestie, welcome to getfsent(3), straight out of the Library Functions Manual 💖 this is the girlies who read /etc/fstab for you so you don't have to, and honestly? iconic behaviour.

---

🌸 NAME 🌸

getfsent, getfsspec, getfsfile, setfsent, endfsent — handle fstab entries 💅

📚 LIBRARY 📚

Standard C library (libc, -lc) 🫶

🎀 SYNOPSIS 🎀

#include <fstab.h>

int setfsent(void);
struct fstab *getfsent(void);
void endfsent(void);

struct fstab *getfsfile(const char *mount_point);
struct fstab *getfsspec(const char *special_file);

🦋 DESCRIPTION 🦋

so these functions read from the file /etc/fstab, no cap. and the struct fstab is defined like this:

struct fstab {
    char       *fs_spec;       /* block device name */
    char       *fs_file;       /* mount point */
    char       *fs_vfstype;    /* filesystem type */
    char       *fs_mntops;     /* mount options */
    const char *fs_type;       /* rw/rq/ro/sw/xx option */
    int         fs_freq;       /* dump frequency, in days */
    int         fs_passno;     /* pass number on parallel dump */
};

the way that fs_type field is doing the most — on a *BSD system it holds one of these five strings: "rw", "rq", "ro", "sw", "xx". and what do those mean? read-write, read-write with quota, read-only, swap, ignore. periodt. 💀

• setfsent() — opens the file when required and positions it at the first line. main character energy fr.
• getfsent() — parses the next line from the file. (and yes, it opens the file first when required 🙈)
• endfsent() — closes the file when required. bye bestie 👋
• getfsspec() — searches the file from the start and returns the first entry it finds where the fs_spec field matches the special_file argument.
• getfsfile() — searches the file from the start and returns the first entry it finds where the fs_file field matches the mount_point argument.

---

💖 RETURN VALUE 💖

upon success, getfsent(), getfsfile(), and getfsspec() hand you back a pointer to a struct fstab, while setfsent() returns 1 — slay ✨

upon failure or end-of-file, these functions return NULL and 0, respectively. not slay. 😭

👑 ATTRIBUTES 👑

for an explanation of the terms used in this section, go peek at attributes(7) 🌈

• endfsent(), setfsent() — Thread safety: MT-Unsafe race:fsent
• getfsent(), getfsspec(), getfsfile() — Thread safety: MT-Unsafe race:fsent locale

🌈 VERSIONS 🌈

several operating systems have these functions, for example *BSD, SunOS, Digital UNIX, and AIX — and AIX also has a getfstype() like okay girl, overachiever 💅

HP-UX has functions of the same names, except they use a struct checklist instead of a struct fstab, and it calls these functions obsolete, superseded by getmntent(3). oop 👀

⭐ STANDARDS ⭐

None. literally none. free spirit fr fr.

🕰️ HISTORY 🕰️

the getfsent() function appeared in 4.0BSD; the other four functions appeared in 4.3BSD. old ones, but they ate. 💜

💀 NOTES 💀

these functions are not thread-safe. no cap.

since Linux allows mounting a block special device in several places, and since several devices can have the same mount point — where the last device with a given mount point is the interesting one — while getfsfile() and getfsspec() only return the first occurrence, these two functions are not suitable for use under Linux. so like, heads up bestie, this is a whole real limitation, not me being dramatic 🫶

🔥 SEE ALSO 🔥

getmntent(3), fstab(5)

---

and that's the whole page, bestie!! 🎀 this one's from Linux man-pages 6.20, dated 2026-02-08 — tysm for reading, go mount something responsibly 💖✨🦋