getpwent(3C) (C Programming Language Utilities) getpwent(3C)
NAME
getpwent, getpwuid, getpwnam, setpwent, endpwent, fgetpwent -
manipulate password file entry
SYNOPSIS
#include <pwd.h>
struct passwd *getpwent (void);
struct passwd *getpwuid (uidt uid);
struct passwd *getpwnam (const char *name);
void setpwent (void);
void endpwent (void);
struct passwd *fgetpwent (FILE *f);
DESCRIPTION
getpwent, getpwuid and getpwnam each returns a pointer to an object
with the following structure containing the broken-out fields of a
line in the /etc/passwd file. Each line in the file contains a
passwd structure, declared in the pwd.h header file:
struct passwd {
char *pwname;
char *pwpasswd;
uidt pwuid;
gidt pwgid;
char *pwage;
char *pwcomment;
char *pwgecos;
char *pwdir;
char *pwshell;
};
getpwent when first called returns a pointer to the first passwd
structure in the file; thereafter, it returns a pointer to the next
passwd structure in the file; so successive calls can be used to
search the entire file. getpwuid searches from the beginning of the
file until a numerical user id matching uid is found and returns a
pointer to the particular structure in which it was found. getpwnam
searches from the beginning of the file until a login name matching
name is found, and returns a pointer to the particular structure in
which it was found. If an end-of-file or an error is encountered on
reading, these functions return a NULL pointer.
A call to setpwent has the effect of rewinding the password file to
allow repeated searches. endpwent may be called to close the
password file when processing is complete.
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getpwent(3C) (C Programming Language Utilities) getpwent(3C)
fgetpwent returns a pointer to the next passwd structure in the
stream f, which matches the format of /etc/passwd.
FILES
/etc/passwd
SEE ALSO
getlogin(3C), getgrent(3C).
passwd(4) in the System Administrator's Reference Manual.
DIAGNOSTICS
getpwent, getpwnid, getpwnam, and fgetpwent return a null pointer on
EOF or error.
NOTES
All information is contained in a static area, so it must be copied
if it is to be saved.
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